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Mammal  Collectors'  Manual 


D.  W.  Nagorsen  and  R.  L.  Peterson 


p.s. 

Ro 
690 
N34 
1980 


Digitized  by  the  Internet  Archive 

in  2012  with  funding  from 

Royal  Ontario  Museum 


http://archive.org/details/mammalcollectorsOOnago 


LIFE  SCIENCES  MISCELLANEOUS  PUBLICATIONS 
ROYAL  ONTARIO  MUSEUM 


d.w.nagorsen  Mammal  Collectors'  Manual 

R.  L.  PETERSON 


A  Guide  for  Collecting,  Documenting, 
and  Preparing  Mammal  Specimens 
for  Scientific  Research 


Publication  date:  6  June  1980 
ISBN  0-88854-255-0 
ISSN  0082-5093 


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V 


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ROYAL  ONTARIO  MUSEUM 
PUBLICATIONS  IN  LIFE  SCIENCES 

The  Royal  Ontario  Museum  publishes  three  series  in  the  Life  Sciences: 

life  sciences  contributions,  a  numbered  series  of  original  scientific  publications  including  monographic 
works. 

life  sciences  occasional  papers,  a  numbered  series  of  original  scientific  publications,  primarily  short  and 
usually  of  taxonomic  significance. 

life  sciences  miscellaneous  publications,  an  unnumbered  series  of  publications  of  varied  subject  matter 
and  format. 

All  manuscripts  considered  for  publication  are  subject  to  the  scrutiny  and  editorial  policies  of  the  Life 
Sciences  Editorial  Board,  and  to  review  by  persons  outside  the  Museum  staff  who  are  authorities  in  the 
particular  field  involved. 


LIFE  SCIENCES  EDITORIAL  BOARD 

Senior  Editor:  R  d  james 
Editor:  c  McGOwan 
Editor:  p  h  von  bitter 

d  w  nagorsen  is  a  Curatorial  Assistant  in  the  Department  of  Mammalogy,  Royal  Ontario  Museum. 
R   L   Peterson  is  Curator-in-charge  in  the  Department  of  Mammalogy,  Royal  Ontario  Museum,  and 
Professor  in  the  Department  of  Zoology,  University  of  Toronto. 


Cover:  A  hoary  bat  (Lasiurus  cinereus)  and  a  deer  mouse  (Peromyscus  maniculatus) 


Canadian  Cataloguing  in  Publication  Data 

Nagorsen,  David  W. 

Mammal  collectors'  manual 

(Life  sciences  miscellaneous  publications  ISSN 
0082-5093) 

Bibliography:  p. 

ISBN  0-88854-255-0  pa. 

1 .  Mammals  —  Collection  and  preservation  — 
Handbooks,  manuals,  etc.  I.  Peterson,  Randolph 
L.,  1920-      II.  Royal  Ontario  Museum.  III.  Title. 
IV.  Series:  Life  sciences  miscellaneous  publication. 


QL708.4.N34 
QL1.T6539 


579'.02'02 


C80-094365-1 


©  The  Royal  Ontario  Museum,  1980 

100  Queen's  Park,  Toronto,  Canada  M5S  2C6 

PRINTED  AND  BOUND  IN  CANADA  AT  THE  ALGER  PRESS 


Contents 

1.  Introduction     5 

2.  Collecting  Policy     6 

2.1  Collecting  Laws     6 

2.2  Firearms     7 

2.3  Collecting  Ethics     8 

3.  Methods  for  Collecting  Mammals     8 

3.1  Bats     8 

A.  Equipment     8 

B.  Collecting  Techniques     11 

3.2  Other  Small  Mammals     12 

3.3  Fur-bearers  and  Large  Mammals     16 

4.  Documenting  Specimens     17 

4.1  Recording  Data     17 

4.2  Specimen  Tags     19 

4.3  Measurements  and  Weights     22 

4.4  Determining  the  Sex  of  Mammals     26 

4.5  Reproductive  Data     30 

A.  Males     31 

B.  Females     31 

4.6  Locality  Descriptions     32 

4.7  Habitat  Descriptions     34 

4.8  Methods  of  Capture     35 

4.9  Miscellaneous  Field  Notes     35 

4. 10  Photographic  Records     35 

5.  Methods  for  Preparing  Specimens     36 

5.1  Preserving  in  Fluid     36 

5.2  Preparing  Skins     38 

A.  Study  Skins     39 

B.  Flat  Skins     54 

C.  Skins  to  be  Tanned     57 

5.3  Preparing  Skulls     60 

5.4  Preparing  Skeletons     60 

6.  Special  Techniques     61 

6.1  Karyotyping     61 

6.2  Collecting  Parasites     63 

6.3  Tissues  for  Biochemical  Study     64 

6.4  Blood  Samples     65 

6.5  Preserving  Stomach  Contents     66 

6.6  Preparation  of  Sperm  Slides     66 

6.7  Fixing  Tissues  for  Histological  Study     67 

7.  Shipping  Specimens     68 

7. 1  Methods  for  Shipping.    68 

7.2  Import/Export  Regulations     70 

8.  Public  Health  Hazards     72 


9.  Acknowledgements     72 

10.  Selected  Bibliography     73 

1 1 .  Appendices     77 

11.1  Appendix  1 :  Checklist  of  Field  Equipment     77 

11.2  Appendix  2:  Karyotype  Kit  for  120  Small  Mammals     78 


Mammal  Collectors'  Manual 


1 .     Introduction 


In  1965,  one  of  the  authors  (R.L.P.)  prepared  a  pamphlet  Collecting  Bat  Specimens 
for  Scientific  Purposes,  in  which  procedures  were  outlined  for  collecting,  measuring, 
preparing,  and  shipping  specimens.  The  usefulness  of  that  leaflet  prompted  us  to 
expand  the  concept  into  a  more  detailed  book  that  includes  most  mammals.  Our 
intention  here  is  not  to  encourage  indiscriminate  collecting.  Rather  the  purpose  of  the 
manual  is  to  provide  a  guide  that  will  serve  as  a  set  of  standards  for  anyone  collecting 
mammals  for  scientific  specimens.  By  following  the  guidelines  in  this  manual, 
specimens  and  associated  data  should  have  maximum  value  for  research.  In  addition 
to  museum  biologists  and  mammalogy  students,  the  guide  should  be  useful  to 
ecologists,  biologists  involved  in  environmental  impact  studies,  parasitologists, 
cytogeneticists,  and  other  laboratory  scientists  who  may  find  it  necessary  to  prepare 
voucher  specimens  for  their  research.  Naturalists  and  wildlife  biologists  wanting  to 
prepare  museum  specimens  from  rare  or  unusual  mammals  obtained  from  hunters, 
trappers,  or  road  kills  should  also  find  the  manual  helpful. 

Several  general  guides  already  exist  for  the  mammal  collector.  These  include  Hall 
(1962),  Anderson  (1965),  Setzer  (1968),  Giles  (1971),  and  DeBlase  and  Martin 
(1974).  However,  several  of  these  publications  are  now  out  of  date  and  do  not 
describe  the  newer  techniques  available.  Also,  the  kinds  of  field  data  that  should  be 
recorded  may  be  given  only  cursory  coverage.  A  number  of  specialized  papers  (see 
bibliography)  dealing  with  collecting  techniques  for  specific  mammals  or  field  data 
(reproductive  data,  locality  descriptions)  exist  in  various  scientific  journals. 
However,  the  average  collector  may  be  unaware  of  these  publications.  Therefore,  we 
have  attempted  to  produce  an  up-to-date  guide  on  the  methods  for  collecting, 
preparing,  and  documenting  mammal  specimens  by  combining  methods  derived  from 
our  own  field  experience  and  from  the  published  sources  listed  in  the  bibliography. 

The  recording  of  field  data  is  strongly  emphasized  in  the  manual.  In  1972  the 
Department  of  Mammalogy  at  the  ROM  initiated  a  computerized  cataloguing  system 
for  storing  and  retrieving  specimen  data.  With  this  system,  it  is  now  possible  to 
process  a  large  quantity  of  data  for  each  specimen.  In  addition  to  standard 
measurements,  information  on  weight,  sex,  age,  date,  reproductive  data,  habitat 
description,  and  a  precise  locality  description,  including  latitude  and  longitude,  are 
stored  on  magnetic  tape.  Other  institutions  with  major  mammal  collections  have  also 
begun  to  use  similar  computer  systems  and  it  is  possible  that  in  the  future  most 
museum  catalogue  records  may  be  stored  in  a  central  data  bank.  To  utilize  fully  the 
potential  of  these  cataloguing  systems,  collectors  should  provide  the  maximum 
amount  of  data  for  specimens. 


With  an  increasing  concern  for  the  conservation  of  mammalian  species  and  the 
additional  restrictions  being  placed  on  collectors,  it  is  most  important  that  a 
reasonable  and  responsible  collecting  policy  be  followed.  Collecting  ethics  and 
collecting  laws  are  discussed  in  section  2.  The  recent  proliferation  of  import/export 
regulations  for  scientific  specimens  is  another  area  of  concern  for  collectors. 
Canadian  and  US  import/export  regulations  are  discussed  in  some  detail  in  section  7. 
Collectors  are  urged  to  read  these  two  sections  carefully  before  collecting  specimens. 


2.     Collecting  Policy 


2.1     Collecting  Laws 

In  recent  years  there  has  been  a  great  increase  in  the  number  of  collecting  laws  and 
endangered  species  acts  that  directly  affect  the  scientific  collector.  These  laws  may  be 
complex  and  ambiguous  and  obtaining  the  necessary  permits  for  collecting  in  an  area 
may  involve  considerable  bureaucracy.  Nevertheless,  the  collector  has  an  obligation 
to  learn  and  comply  with  these  laws  and  regulations.  It  is  essential  that  permits  be 
obtained  prior  to  any  field  collecting.  Mammals  that  are  protected  under  endangered 
species  legislation  should  not  be  disturbed  or  collected  except  under  special  permit. 

Canada 

In  Canada,  a  Scientific  Collector's  Licence  issued  by  the  various  provincial  and 
territorial  governments  is  needed.  Fur-bearers  and  game  species  are  usually  regulated 
under  provincial  Game  Acts  and  Regulations  and  special  permission  may  be 
necessary  for  collecting  these  species.  Additional  permits  may  be  needed  to  work  in  a 
provincial  park.  In  Ontario,  for  example,  collectors  who  plan  to  work  in  provincial 
parks  must  have  their  research  proposal  approved  by  the  District  Manager  and  the 
Director  of  the  Parks  Branch,  Ministry  of  Natural  Resources.  Permission  from  the 
federal  government  is  required  for  collecting  in  national  parks.  Some  provinces  and 
territories  also  require  permits  for  salvaging  dead  mammals  or  parts  thereof 
(carcasses,  bones,  shed  antlers).  For  more  information,  consult  the  appropriate 
provincial  or  territorial  governments. 

Although  Canada  has  no  federal  endangered  species  act,  Canada  has  signed  the 
Convention  on  International  Trade  in  Endangered  Species  (see  section  7.2).  Ontario 
and  New  Brunswick  have  passed  provincial  endangered  species  legislation. 

United  States 

The  US  laws  are  complex  and  involve  state  and  federal  authorities.  Generally, 
wildlife  is  regulated  by  the  state  governments  and  the  collector  should  contact  the 
appropriate  state  governmental  agency  for  permits.  To  collect  scientific  specimens  in 
a  national  refuge  or  in  a  national  park,  a  permit  issued  by  the  Refuge  Manager  or  the 


Superintendent  of  the  national  park  is  necessary.  Permits  to  collect  in  national  parks 
are  issued  only  to  persons  officially  representing  reputable  scientific  institutions  and 
annual  reports  are  required.  Although  state  and  federal  requirements  for  scientific 
collecting  must  be  met,  special  permits  are  not  needed  for  collecting  in  national  forest 
systems.  Collectors,  however,  are  requested  to  contact  the  local  Forest  Service 
District  Ranger  before  initiating  any  fieldwork. 

Marine  mammals  are  covered  under  the  Marine  Mammal  Protection  Act.  You  may 
take  and  process  marine  mammals  and  parts  thereof  (bones,  teeth,  ivory)  only  under 
permit.  Walruses  (Qdobenus  rosmarus),  sea  otters  (Enhydra  lutris),  polar  bears 
(Ursus  maritimus),  and  manatees  (Trichechus  sp.)  are  under  the  jurisdiction  of  the 
Director  of  the  US  Fish  and  Wildlife  Service.  Cetaceans  and  all  pinnipeds  (except 
walruses)  are  under  the  authority  of  the  Director  of  the  National  Marine  Fisheries 
Service. 

Collectors  working  in  the  US  should  be  aware  that  endangered  and  threatened 
species  are  protected  at  both  the  federal  and  state  levels.  The  federal  Endangered 
Species  Act  that  took  effect  in  1977  prohibits  the  taking  and  capture  of  all  listed 
mammals  as  well  as  the  import  and  export  of  these  species.  Species  protected  under 
the  Act  are  listed  as  either  "endangered"  or  "threatened".  The  various  prohibitions 
of  the  Act  apply  to  live  or  dead  mammals  and  their  parts  or  products.  If  you  plan  to 
salvage  or  utilize  dead  mammals  listed  in  the  Act,  you  must  have  a  permit  issued  by 
the  Director  of  the  US  Fish  and  Wildlife  Service,  or  if  endangered  marine  mammals, 
from  the  Director  of  National  Marine  Fisheries  Service.  For  further  information, 
contact  the  Federal  Wildlife  Permit  Office,  US  Fish  and  Wildlife  Service, 
Washington,  DC  20240.  Some  states  have  also  passed  endangered  species  legislation 
and  mammals  protected  under  state  law  may  or  may  not  be  the  same  as  those  listed 
under  the  federal  Endangered  Species  Act.  Information  on  these  state  laws  can  be 
obtained  from  the  appropriate  state  governmental  authorities  such  as  conservation  or 
wildlife  departments  (see  McGaugh  and  Genoways  1976). 

Other  Countries 

Many  other  countries  have  also  passed  endangered  species  legislation  and  regulations 
for  the  collecting  of  scientific  specimens.  Collectors  planning  to  work  abroad  should 
contact  the  governmental  agencies  in  these  countries  well  in  advance  of  any  field  trip. 
It  is  essential  that  one  understand  the  regulations  in  these  countries  and  obtain  the 
necessary  permits  before  any  field  collecting.  Moreover,  export  permits  may  be 
required  in  some  countries  for  transporting  specimens  out  of  these  countries. 

The  collector  should  also  be  aware  of  the  Convention  on  International  Trade  in 
Endangered  Species.  Even  if  species  listed  in  the  Convention  are  not  protected  in  the 
country  where  the  collector  is  working,  it  may  be  impossible  to  import  specimens  of 
species  listed  in  the  Convention  into  North  America  without  permits  (see  section  7). 

2.2     Firearms 

In  recent  years  there  has  been  a  growing  anti-hunting  sentiment  and  collectors 
therefore  are  urged  to  use  discretion  when  collecting  with  guns.  Handguns  are  strictly 
controlled  in  Canada  and  permits  issued  by  police  departments  are  required.  In  some 
provinces  municipal  or  provincial  police  departments  may  issue  permits;  in  other 


provinces,  the  Yukon,  and  the  Northwest  Territories,  permits  are  issued  by  the  Royal 
Canadian  Mounted  Police  (RCMP).  In  the  US,  firearms  are  generally  regulated  by  the 
various  state  governments  and  collectors  should  consult  their  state  or  local  police 
departments  for  information.  When  planning  to  use  firearms  in  foreign  countries, 
investigate  thoroughly  the  various  laws  in  these  countries  pertaining  to  firearms  and 
ammunition.  These  laws  include  customs  regulations  covering  the  importation  of 
guns  and  ammunition. 

2.3     Collecting  Ethics 

The  possession  of  a  valid  collecting  permit  does  not  give  the  collector  the  right  to  use 
irresponsible  collecting  methods.  Specimens  should  be  collected  in  the  most  humane 
method  possible  and  any  damage  or  destruction  to  the  local  biota  or  collecting  sites 
must  be  prevented.  Indiscriminate  collecting  of  excessive  numbers  is  discouraged, 
particularly  in  areas  where  large  numbers  may  concentrate.  When  possible,  take 
mammals  alive  and  once  the  required  sample  has  been  collected,  release  the 
remaining  mammals  unharmed.  Obviously  with  techniques  such  as  snap  trapping  this 
procedure  is  impossible  to  follow.  Specimens  acquired  for  systematic  collections 
should  be  carefully  prepared  and  thoroughly  documented  using  the  standards  outlined 
in  this  manual. 

Systematic  research  on  a  species  requires  a  statistically  adequate  number  of 
specimens  from  various  localities.  Because  some  species  are  sexually  dimorphic 
(e.g.,  one  sex  may  be  consistently  larger  than  the  other),  a  representative  series 
should  contain  samples  of  both  sexes.  For  a  given  locality,  10  to  15  adults  of  each  sex 
are  usually  an  adequate  number  for  a  species.  A  few  young  animals  in  each  sample 
may  be  useful  for  studying  growth  and  age  variation. 

To  study  geographic  variation  in  a  species,  representative  samples  from  various 
localities  throughout  the  geographic  range  of  the  species  are  required.  Distance 
between  collecting  sites  is  a  function  of  habitat  diversity  in  a  given  area  and  in  regions 
with  homogeneous  biomes  and  habitats  (e.g.,  the  boreal  forest  in  northern  Canada  or 
the  tropical  rain  forest  in  the  Amazon  basin)  localities  may  be  15  to  160  km  (10-100 
miles)  apart.  But  in  regions  that  support  a  diversity  of  biomes  and  habitats  (e.g., 
mountainous  regions  or  river  systems),  collecting  sites  may  need  to  be  close  together, 
8  km  (5  miles)  or  less. 


3.     Methods  for  Collecting  Mammals 


3.1     Bats 

A.     Equipment 

mist  NETS 

Mist   nets  or  bird-banders'    nets  (Bleitz   Wildlife   Foundation,   5334   Hollywood 
Boulevard,  Hollywood,  California,  USA)  are  effective  for  capturing  bats  alive.  The 

8 


nets  consist  of  a  fine  nylon  mesh  (50  or  70  denier)  thread  with  mesh  consisting  of 
36  mm  (1.5  inch)  squares  fitted  on  a  string  frame  that  divides  the  net  into  panels. 
Loops  of  cord  at  the  end  of  each  panel  hold  the  net  on  supports  such  as  long  slender 
poles  of  bamboo  cane  (Fig.  1). 

In  tropical  regions  a  machete  is  useful  to  cut  and  trim  suitable  poles  and  to  clear 
vegetation.  To  set  the  net,  secure  one  pole  in  the  ground.  Usually  the  pole  can  be 
driven  into  the  ground  by  repeated  jabbing  and  twisting,  however,  you  may  have  to 
provide  additional  support  by  piling  rocks  against  the  base  of  the  pole  or  by  attaching 
guys  of  cord  to  nearby  trees  or  stakes.  Place  the  loops  of  one  end  of  the  net  in  proper 
sequence  over  the  pole  and  unfold  the  net,  keeping  it  taut  and  off  the  ground.  When 
the  net  is  completely  unfolded,  erect  the  second  pole  and  slip  the  loops  over  it.  Once 
on  the  poles,  the  net  is  opened  by  spacing  the  panel  strings  at  intervals  along  the  pole. 
It  is  important  that  the  net  be  taut  enough  to  prevent  sagging  but  loose  enough  to 
provide  adequate  pockets  to  stop  bats  from  bouncing  off  the  net.  Remove  any  leaves, 
sticks,  or  insects  that  may  become  entangled  in  the  net.  Although  the  poles  and  net 
should  be  set  and  adjusted  before  dark,  the  net  should  not  be  opened  on  the  poles  until 
the  collector  intends  to  use  it.  This  will  prevent  the  capture  of  birds  that  are  frequently 
active  several  hours  before  sunset.  It  is  important  to  check  nets  frequently  and 
regularly  and  to  remove  netted  bats,  as  large  bats  can  cause  extensive  damage  by 
chewing  themselves  free.  To  catch  species  that  are  adept  at  freeing  themselves 
without  entanglement,  it  is  necessary  to  actually  stand  by  the  net  and  remove  bats  as 
they  hit  the  net.  This  is  particularly  true  for  some  of  the  small,  African  free-tailed  bats 
(Molossidae).  Constant  attention  is  also  necessary  in  agricultural  areas  where 
domestic  animals  may  wander  into  untended  mist  nets. 

Equipment  required  to  attend  nets  includes:  a  headlight  with  spare  batteries  and 
bulbs,  a  flashlight,  collecting  bags,  gloves,  nylon  fishing  line  to  repair  broken  shelf 


Fig.    1     A  four-panel  mist  net  (12.5  m  x  2  m;  42  ft  x  7  ft)  set  on  poles. 


strings,  cord  or  rope  for  guy  lines,  and  a  knife  or  scissors  for  cutting  badly  entangled 
bats  from  the  net. 

To  remove  a  bat  from  the  net,  determine  first  the  side  from  which  it  entered.  With 
the  bat  held  firmly  in  the  gloved  hand,  use  the  ungloved  hand  to  remove  the  bat  from 
the  open  side  of  the  pocket,  beginning  with  the  head.  The  best  method  is  to  remove 
netting  from  the  bat's  mouth  first  and  then  work  back,  freeing  the  wings  and  feet. 
Once  removed  from  the  net,  bats  can  be  kept  alive  in  cloth  collecting  bags  about 
35  cm  x  20  cm  (14  inches  x  18  inches).  Use  several  bags  and  keep  the  larger  species 
separate  from  the  smaller  ones.  If  bats  are  not  prepared  immediately  as  specimens, 
they  can  be  kept  alive  overnight  in  these  bags.  To  increase  the  chance  of  survival, 
keep  the  bags  in  a  cool,  well-ventilated  place. 

Nets  should  be  taken  down  before  dawn  to  avoid  catching  birds  and  diurnal  insects. 
First,  remove  all  leaves  or  sticks,  then  slide  the  string  loops  together  on  the  poles  to 
close  the  net.  In  areas  where  theft  is  not  a  problem,  nets  may  be  closed  and  left  on  the 
poles  during  the  day.  When  the  net  is  to  be  removed  from  the  poles,  tie  a  piece  of 
string  to  the  top  loop  of  each  end  and  pass  this  string  through  all  the  loops  to  keep 
them  in  proper  sequence.  Then  remove  the  net  from  one  pole  and  walk  towards  the 
other  pole  collecting  and  folding  the  net  in  your  hands.  The  net  can  then  be  doubled  or 
redoubled  into  a  compact  bundle  and  stored  in  a  plastic  bag. 

HAND  NETS 

An  insect  net  with  a  long,  extensible  aluminium  handle  (no.  324  Tropics  net, 
BioQuip  Products,  P.O.  Box  681,  Santa  Monica,  California,  USA)  is  useful  to 
collect  bats  in  caves,  mines,  and  buildings.  This  particular  net  has  a  4  m  (12  ft) 
handle  composed  of  six  pieces,  each  60  cm  (2  ft)  in  length,  which  screw  together.  An 
ordinary  insect  net  can  be  modified  for  bat  collecting  by  making  a  long  handle  of 
suitable  material.  You  can  also  improvise  with  a  coat  hanger  or  a  wire  of  similar 
gauge  bent  into  a  hoop  and  laced  with  mosquito  netting  or  cheesecloth. 

SHOOTING 

Although  less  preferable  to  netting  because  of  potential  specimen  damage,  shooting  is 
a  useful  technique  for  collecting  some  of  the  sac-winged  (Emballonuridae), 
vespertilionid  (Vespertilionidae),  and  free-tailed  (Molossidae)  bats  that  are  difficult 
to  net  because  they  forage  above  the  tree  canopy  and  for  bats  that  roost  in  large  caves 
with  high  ceilings  or  in  tall  palm  trees.  For  minimum  damage  to  specimens,  use  fine 
shot  (no.  12  shot)  loaded  in  .22  or  .32  calibre  rifle  shells  or  in  .410  gauge  shotgun 
shells.  For  best  results  .22  rifle  shells  loaded  with  no.  12  shot  should  be  used  in  a 
special  smooth  bore  .22  gun.  Auxiliary  barrels  ("Aux.")  that  slip  into  20,  16,  or  12 
gauge  shotgun  chambers  are  made  for  holding  .32  gauge  or  .410  gauge  shells  loaded 
with  no.  12  shot. 

BAT  TRAPS 

Several  designs  for  bat  traps  have  been  used  but  one  of  the  most  versatile  is  the  Tuttle 
trap.  This  trap  consists  of  two  rectangular  aluminium  frames  that  support  vertical  wire 
strands.  Bats  collide  with  the  wires  and  fall  unharmed  into  a  canvas  collecting  bag. 
The  Tuttle  trap  is  not  available  commercially;  however,  for  a  description,  including 
specifications  for  construction,  see  Tuttle  (1974).  In  arid  regions  with  restricted 

10 


water,  a  single  strand  of  fine  piano  wire  can  be  stretched  across  a  pond  or  water  tank 
about  20  cm  (6  inches)  above  the  water.  Bats  striking  the  wire  will  fall  into  the  water. 
As  bats  swim  to  shore,  they  can  be  captured  with  a  hand  net. 

B.     Collecting  Techniques 

Bats  are  collected  primarily  from  diurnal  roosts  and  from  foraging  or  drinking  sites  at 
night. 

ROOSTS 

Caves  and  Mines 

Caves  and  mines  (especially  abandoned  ones)  are  usually  productive  sites  for  the  bat 
collector.  Larger  caves  or  mines  that  may  contain  bats  may  be  located  from 
large-scale  topographic  maps  (1:50  000),  which  usually  indicate  cave  or  mine  sites, 
and  by  questioning  local  residents.  The  collector  may  save  considerable  time  and 
effort  by  hiring  a  local  person  familiar  with  a  particular  mine  or  cave  to  act  as  a  guide. 
The  cave  or  mine  should  be  entered  slowly  with  a  minimal  amount  of  noise.  Some 
species  roost  in  dim  areas  near  the  entrance;  others  prefer  dark  areas  deep  within. 
Examine  each  hole  or  depression  in  the  roof  as  well  as  side  openings  while  listening 
for  vocalizations  or  for  sounds  of  flying  bats.  Bats  roosting  on  the  ceiling  may  be 
taken  in  a  long-handled  insect  net  or  shot — if  there  appears  to  be  no  danger  of  the 
ceiling's  collapsing.  Bats  flying  about  can  be  captured  in  bat  traps  or  with  small 
pieces  (1  m;  2-4  ft)  of  old  mist  net  strung  across  corridors.  Mist  nets  set  near  the  cave 
or  mine  entrance  before  dusk  may  capture  large  numbers  of  bats  as  they  leave  to 
forage. 

Buildings 

Many  bats,  particularly  some  vespertilionids  (Vespertilionidae)  and  free-tailed  bats 
(Molossidae)  roost  in  tile,  thatched,  or  metal  roofs,  attics,  and  cavities  between  walls 
of  buildings.  Local  inhabitants  can  usually  provide  information  on  buildings  that 
contain  bat  colonies.  Bats  roosting  in  buildings  may  often  be  captured  by  hand  (use 
gloves),  with  hand  nets,  or  with  long  forceps  (25  cm;  10  inches)  that  will  reach  into 
holes  and  crevices.  If  you  cannot  capture  bats  from  buildings  during  the  day,  it  may 
be  possible  to  collect  them  with  mist  nets,  hand  nets,  or  bat  traps  as  they  leave  the 
building  to  forage  at  night.  By  carefully  observing  the  building  in  the  evening,  you 
can  usually  locate  the  openings  that  bats  are  using  for  exits. 

Other  Roosts 

During  the  day,  some  bats  roost  in  hollow  trees  or  logs,  under  the  bark  of  trees,  in 
rock  crevices,  under  large  leaves  such  as  palm  or  banana  fronds,  in  culverts,  under 
bridges,  and  even  under  rocks  or  stones.  Migrating  tree  bats  and  Old  World  fruit  bats 
may  hang  from  trees  and  bushes  in  open,  exposed  areas. 

FORAGING  SITES 

Although  foraging  bats  can  be  collected  with  traps  or  by  shooting,  generally  the  most 

11 


effective  technique  is  mist  netting.  To  net  foraging  bats  efficiently,  the  collector 
should  become  familiar  with  the  most  productive  areas.  Many  species  can  be  netted 
near  their  feeding  sites  (orchards,  wild  fruit  trees,  flowering  shrubs,  trees,  and  over 
ponds  or  streams).  Forest  trails,  the  edges  of  forested  areas,  and  highland  passes  are 
often  used  by  bats  as  natural  fly  ways.  Isolated  ponds  in  arid  regions  may  attract  great 
numbers  of  bats,  particularly  during  the  dry  season.  Nets  set  over  streams  or  forest 
trails  should  be  positioned  in  narrow  areas  where  natural  obstacles  funnel  bats  into  the 
net.  Factors  that  will  reduce  netting  success  are  rain,  heavy  dew,  and  moonlight. 
Some  experimenting  with  the  height  of  the  net  above  the  ground,  the  angle  of  the  net 
relative  to  a  flyway  and  its  position  relative  to  surrounding  vegetation  is  necessary  to 
obtain  satisfactory  results  in  different  localities.  Many  species  fly  just  above  the 
ground  vegetation  so  that  nets  set  with  the  bottom  strand  about  20  cm  (6  inches) 
above  the  ground  is  a  good  starting  point  from  which  to  experiment. 


3.2     Other  Small  Mammals 


Snap  Traps 

The  most  successful  trap  for  catching  small  rodents,  marsupials,  and  insectivores  is 
the  snap  trap.  These  traps  are  generally  sold  commercially  (Victor  Traps,  Litiz, 
Pennsylvania,  USA)  in  mouse-trap  and  rat-trap  sizes.  The  larger,  more  powerful 
rat-trap  is  designed  for  killing  mammals  the  size  of  rats  and  small  squirrels.  Designed 
for  mammals  of  shrew  and  mouse  size,  the  smaller  mouse-trap  is  more  effective,  but 
the  spring  bar  on  the  trap  frequently  crushes  the  skull  of  the  specimen. 

Most    collectors    prefer    the    Museum    Special    model    (Fig.    2)    (Woodstream 
Corporation,  Litiz,  Pennsylvania,  USA).  This  trap  is  intermediate  in  size  between  the 


Fig.   2     Museum  special  snap  trap  shown  in  the  set  position.  Trap  size  is  14  cm  x  7  cm  (5.5 
inches  x  2.7  inches). 


12 


mouse-  and  rat-trap  and  it  is  designed  to  kill  mammals  weighing  up  to  50  g  (2  oz). 
Advantages  of  this  trap  are  an  extremely  sensitive  trigger  mechanism  and  a  spring  bar 
designed  to  break  the  specimen's  back  rather  than  to  crush  the  skull.  Equipped  with  a 
weak  spring,  this  trap  can  be  used  to  catch  small  mammals  such  as  shrews  without 
seriously  damaging  the  specimen.  Snap  traps  should  be  checked  at  least  once  every 
24  hours,  preferably  in  the  early  morning.  Dead  mammals  decompose  rapidly, 
especially  in  warm  weather.  In  tropical  areas  you  may  have  to  check  traps  more 
frequently  as  ants  may  quickly  eat  specimens. 


Live  Traps 

Live  traps  are  used  to  obtain  live  mammals  for  karyotyping,  biochemical  analyses, 
and  parasite  studies.  Also,  live  traps  permit  the  collector  to  select  only  those 
mammals  required  for  specimens  and  release  others  unharmed.  As  some  animals 
(e.g.,  shrews)  may  be  reluctant  to  enter,  live  traps  are  generally  not  as  effective  as 
snap  traps.  To  sample  the  mammalian  fauna  of  an  area  accurately,  you  should 
supplement  live  trap  lines  with  some  snap  traps. 

For  mammals  such  as  squirrels,  hares,  and  foxes  welded  wire  mesh  traps  are 
available  in  several  sizes  (Havahart  Company,  P.O.  Box  551,  Ossining,  New  York, 
USA;  National  Trap  Corporation,  P.O.  Box  302,  Tomahawk,  Wisconsin,  USA). 
These  traps  usually  have  a  front  and  rear  door  and  are  activated  by  a  bait  pan  in  the 
centre  of  the  trap. 

For  small  rodents  and  some  insectivores  the  most  popular  live  traps  are  the 
Longworth  (Longworth  Scientific  Instrument  Company  Limited,  Thames  Street, 
Abingdon,  Berkshire,  England)  and  the  Sherman  trap  (H.  B.  Sherman  Company, 
Box  683,  DeLand,  Florida,  USA).  The  aluminium  Longworth  trap  has  a  trigger 
mechanism  with  a  detachable  nest  box.  The  Sherman  style  trap,  a  rectangular  box 
constructed  from  aluminium  or  galvanized  metal,  has  a  spring-loaded  treadle  which 
releases  the  door  when  depressed.  An  assortment  of  sizes  and  models,  including 
folding  and  nonfolding  are  available.  We  have  found  a  modification  of  the  Sherman 
trap  (Canadian  Penitentiary  Industries,  Sir  Wilfrid  Laurier  Building,  340  Laurier 
Avenue  West,  Ottawa,  Ontario,  Canada  K1A  0P9)  to  be  effective  in  catching 
mammals  ranging  in  size  from  shrews  to  small  squirrels.  The  trap  is  a  nonfolding  type 
with  a  screened  rear  door  (Fig.  3). 

To  prevent  deaths  in  live  traps,  check  them  at  least  once  daily,  preferably  early  in 
the  morning.  Also  place  some  cotton  wool  for  nesting  material  inside  traps  during 
cool  weather. 


Bait 

An  effective  bait  for  small  mammals  that  can  be  used  in  snap  traps  or  live  traps  is  a 
mixture  of  peanut  butter  and  rolled  oats.  Chopped  nuts,  seeds,  bits  of  chopped  fruit 
(apples,  raisins,  bananas),  or  cheese  can  be  added  to  this  mixture.  Experiment  with 
different  combinations  of  bait  to  determine  the  one  most  effective  in  a  particular  area. 
Plastic  containers  with  screw-top  lids  or  plastic  squeeze  tube  containers  are  useful  for 
carrying  premixed  bait  when  checking  traps. 

13 


--;>, 


Fig.   3     Nonfolding  type  of  Sherman  live  trap  with  screened  rear  door.  Trap  size  is  30  cm  x 
8  cm  x  8  cm  (12  inches  x  3  inches  x  3  inches). 


Special  Traps 

Special  traps  are  made  (Victor  Traps,  Litiz,  Pennsylvania,  USA;  Z.  A.  MacAbee 
Gopher  Trap  Company,  110  Loma  Alta  Avenue,  Los  Gatos,  California,  USA)  for 
capturing  such  fossorial  mammals  as  pocket  gophers  (Geomyidae)  and  moles 
(Talpidae).  Gopher  traps  (Fig.  4)  are  set  in  tunnels  that  are  20  to  900  cm  (6-36 
inches)  below  the  surface  of  the  ground.  Locate  the  shallow  tunnels  near  freshly 
discharged  earth,  remove  a  section  of  the  tunnel,  and  set  a  pair  of  traps  in  each 
direction  in  the  runway.  When  excavating  earth  to  repair  the  opened  tunnel,  the 
pocket  gopher  will  set  off  the  trigger  mechanism  of  the  trap.  To  prevent  traps  from 
being  dragged  into  the  burrow  system,  tie  them  with  wire  to  a  firm  stake. 

Of  the  various  mole  traps  sold  commercially,  the  harpoon  type  (Fig.  5)  appears  to 
be  the  most  efficient.  Push  the  trap  into  the  ground  over  the  mole  tunnel  and  flatten 
the  raised  tunnel  so  that  the  trigger  pan  will  be  set  off  by  the  mole  as  it  moves  through 
the  tunnel.  Consult  Baker  and  Williams  (1972)  for  a  description  of  a  live  trap  for 
gophers  and  Yates  and  Schmidly  (1975)  for  a  mole  live  trap. 

A  simple,  effective  trap  for  shrews  and  certain  species  of  rodents  (e.g.,  jumping 
mice  and  microtine  rodents)  is  a  fruit  juice  or  similar-sized  can  35  cm  x  18  cm  (14 
inches  x  7  inches)  set  flush  with  the  ground.  Cone-shaped  pitfall  traps,  which  have 
the  advantage  of  being  easy  to  carry  in  the  field  because  they  nest  together,  are  sold 
commercially  (Northwest  Metal  Products  Company,  P.O.  Box  10,  Kent, 
Washington,  USA).  It  is  not  necessary  to  bait  pitfall  traps  as  the  mammal  simply 


14 


Fig.  4     Pocket  gopher  trap  in  the  set  position.  Trap  size  is  15  cm  x  5  cm  (6  inches  x  2 
inches). 


tumbles  into  them.  About  75  mm  (3  inches)  of  water  in  the  trap  will  prevent  rodents 
from  jumping  out.  Set  them  adjacent  to  streams,  in  runways,  or  near  burrows  for  best 
results.  When  sampling  a  habitat,  set  at  least  a  few  pitfall  traps  for  they  frequently 
capture  species  not  taken  in  other  types  of  traps. 

Operating  A  Trap  Line 

To  sample  the  small  mammals  of  an  area  thoroughly,  traps  should  be  set  in  a  variety 
of  habitats  (forest,  open  grassy  area,  transition  zones).  The  recommended  procedure 
is  to  set  the  traps  in  a  "trap  line"  at  regular  intervals  and  roughly  in  a  straight  line. 
Trap  sites  are  marked  by  tying  a  piece  of  coloured,  plastic  flagging  tape  or  strip  of 
cloth  to  a  tree  branch  or  a  clump  of  vegetation.  The  total  number  of  traps  in  a  line 
(usually  30-100  traps),  the  number  of  traps  at  each  site,  and  the  spacing  of  traps  is 
determined  by  experience.  For  most  habitats,  you  will  obtain  good  results  by  setting 
traps  about  10  m  (30  ft)  apart  with  two  or  three  traps  at  each  site.  To  be  certain  that  no 
trap  sites  are  missed  when  checking  a  trap  line,  many  collectors  number  their  traps  in 
sequence.  Permanent  numbers  can  be  painted  on  live  traps  and  numbers  can  be 
written  with  a  pencil  on  wooden-based  snap  traps.  Another  method  is  to  write  trap  site 
numbers  on  plastic  flagging  tape  with  a  felt-tipped  marker  pen  (waterproof  ink  type). 

Rather  than  randomly  selecting  trapping  sites,  carefully  choose  the  most  favourable 
microhabitat,  for  example,  the  base  of  trees  or  stumps,  on  top  of  logs,  in  conspicuous 
runways,  at  burrow  entrances,  or  at  the  edge  of  streams  or  ponds.  Many  small 
mammals  confine  their  movements  to  runways  that  appear  as  well  trampled  miniature 
trails  in  the  vegetation.  Other  signs  indicating  the  presence  of  small  mammals  are 
droppings,  tracks,  piles  of  cut  grass  or  sedges,  and  seed  caches.  In  tropical  forests 


15 


Fig.  5     Harpoon  type  of  mole  trap. 
Trap  length  is  40  cm  (16  inches). 


some  species  of  small  mammals  are  arboreal  and  traps  set  in  the  branches  of  trees  will 
catch  species  not  otherwise  taken. 

Shooting 

For  mammals  such  as  rabbits,  squirrels,  and  small-  to  medium-sized  carnivores, 
shooting  may  be  more  effective  and  humane  than  trapping.  To  prevent  excessive 
damage,  use  a  small  gauge  shotgun  (.410  or  20  gauge)  loaded  with  light  shot  instead 
of  a  .22  rifle.  BB  shot  or  no.  2  shot  is  recommended  for  fox-sized  animals,  shot  no.  4, 
6  or  7'/2  is  suitable  for  hare-sized,  and  no.  1 1  or  12  shot  is  used  for  smaller  mammals 
(pikas,  squirrels).  Auxiliary  barrels  are  discussed  in  section  3.1 


3.3     Fur-bearers  and  Large  Mammals 

Steel  leg-hold  traps,  Conibear  traps,  snares,  and  shooting  are  the  usual  methods  for 
collecting  these  mammals  but  check  local  laws  and  regulations  before  doing  so. 
Arrangements  with  experienced  fur  trappers  to  secure  specimens  taken  in  season 
often  provide  good  results.  For  reviews  of  the  techniques  used  for  trapping 
fur-bearers,  consult  The  Manitoba  Trappers'  Guide  (Manitoba  Department  of 
Renewable  Resources  and  Transportation  Service  1965)  or  Stains  (1962). 


16 


4.     Documenting  Specimens 


Described  in  this  section  are  basic  field  data  that  should  be  routinely  recorded  by 
anyone  collecting  mammals  for  scientific  specimens  (field  number,  date  collected, 
nature  of  specimens,  measurements,  sex,  reproductive  data,  locality  descriptions, 
habitat  descriptions,  method  of  capture,  and  miscellaneous  field  notes).  However,  it 
cannot  be  over-emphasized  that  this  information  must  be  accurate.  If  you  are  not 
certain,  do  not  guess!  If  you  are  uncertain  of  the  sex,  for  example,  then  indicate  so 
with  a  question  mark  on  your  catalogue  or  field  notes. 


4.1     Recording  Data 

Collectors  usually  record  their  field  data  in  a  notebook.  DeBlase  and  Martin  (1974) 
and  Hall  (1962)  recommended  that  field  notes  be  organized  into  three  sections:  (1)  a 
journal;  (2)  a  catalogue;  (3)  species  accounts.  At  the  ROM  we  use  a  slightly  different 
system.  Specimen  data  are  recorded  on  printed  catalogue  sheets  (Fig.  6).  Similar  or 
modified  sheets  can  be  designed  to  suit  your  particular  needs.  The  following  is  a  brief 
explanation  of  headings  of  columns  shown  on  the  catalogue  sheet  in  Figure  6. 

The  museum  number  is  assigned  to  the  specimen  when  it  is  accessioned  by  the 
museum,  consequently  leave  this  space  blank.  Each  specimen  listed  in  the  catalogue 
must  have  a  separate  field  number  and  this  number  is  also  written  on  a  tag  (in  pencil 
or  waterproof  ink)  that  is  securely  tied  to  the  corresponding  specimen  (see  section 
4.2).  A  tentative  identification,  even  a  common  name  of  the  specimen,  should  be 
entered  under  the  species  heading.  Always  write  the  date  with  the  month  in  full,  that 
is,  June  10,  1965  not  10/6/65.  Documenting  the  categories  for  sex,  measurements, 
and  locality  are  discussed  in  sections  4.4,  4.3,  and  4.6.  The  nature  of  the  specimen 
(skin  and  skull,  skull  only,  skin  only,  skeleton  only  or  preserved  in  formalin),  should 
also  be  listed  in  the  remarks  for  each  specimen. 

Such  information  as  reproductive  data,  habitat,  and  field  observations  (see  sections 
4.5,  4.7,  and  4.9)  may  be  entered  in  the  remarks  section;  however,  usually  it  is 
impossible  to  fit  all  of  this  information  on  the  catalogue  sheet.  We  recommend  that  a 
field  notebook  or  diary  be  kept  in  conjunction  with  the  catalogue  sheets.  To  ensure 
that  data  are  associated  with  the  appropriate  specimens,  carefully  list  the  field 
numbers  with  their  corresponding  data.  Figure  7  illustrates  a  page  taken  from  a 
typical  field  notebook.  At  the  ROM  we  also  use  printed  sheets  for  recording 
reproductive  data  (Fig.  8).  You  may  wish  to  design  similar  sheets  or  simply  record 
these  data  in  your  notebook. 

All  catalogues,  field  notes,  photographs,  and  maps  of  collecting  sites  are  kept 
permanently  by  museums  as  documentation  for  researchers.  As  catalogue  sheets  and 
field  notes  are  often  the  only  source  of  information  for  specimens,  your  catalogue  and 
notes  should  be  well  organized,  legible,  and  as  accurate  as  possible.  Write  in  pencil 
or  waterproof  ink  as  other  types  of  ink  will  run  if  subjected  to  moisture.  Catalogue 
sheets  or  notes  that  have  been  seriously  damaged  from  moisture,  grease,  or  blood 
should  be  recopied. 

17 


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k>a,t"S  pro  ball  uj  .      Unable.    T^o    ne-+      Hiese. 

Fig.  7     A  page  taken  from  a  field  notebook  of  a  ROM  collector  to  illustrate  the  data  recorded. 
Specimens  are  the  same  as  those  listed  in  the  catalogue  sheet  (Fig.  6). 

4.2     Specimen  Tags 

All  specimens  listed  in  your  catalogue  should  be  labelled  with  their  corresponding 
field  numbers.  DeBlase  and  Martin  (1974)  described  some  of  the  different  kinds  of 
tags  used  by  field  collectors.  ROM  collectors  use  printed  field  number  tags  (Fig.  9d) 
that  are  resistant  to  alcohol  and  formalin  to  label  study  skins,  skulls,  skeletons,  or 

19 


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specimens  in  fluid.  If  these  are  not  available,  you  can  construct  similar  tags  from 
vinyl-coated  paper  or  white  cardboard  (Fig.  9c).  When  labelling  fluid-preserved 
specimens,  ensure  that  tags  are  resistant  to  preserving  solutions.  A  recommended 
method  for  coding  field  numbers  is  to  write  your  initials  preceding  the  specimen 
number  (e.g.,  JHW  237).  This  practice  will  prevent  any  possible  confusion  with 
specimens  of  another  collector. 


bS3> 


B 


DEPARTMENT  OF  MAMMALOGY 


ROYAL  ONTARIO  MUSEUM 


Micro  fus  oecono  mus 


COLLECTOR 


ACCESSION    NO. 


ACQUIRED 


s+*tf 


FIELD  NO. 


12  7&L> 


LOCALITY 


kayFbiniJukon.C*****,    69°/9'M  /38°2n* 


DATE 


Aug./6/7S 


MEASUREMENT 

/GO       3o/9 


/¥ 


SEX 


remarks        tfr  17-Ogms,  Flat  skin  +  skeleton 
+€i.tes     fxG,  young  adult. 


27 


FN  20250 


Fig.  9     Three  types  of  specimen  tags  and  method  for  tying. 

A     Knot  used  for  stringing  study  skin  tag. 

B  Study  skin  label  used  by  many  field  collectors.  Information  recorded  includes 
locality,  date,  sex,  collector's  name,  measurements,  reproductive  data,  identifica- 
tion of  specimen,  and  field  number. 

c  Label  constructed  from  vinyl-coated  paper;  field  number  consists  of  collector's 
initials  and  specimen  number. 

D     Paper  label  (alcohol  and  formalin  resistant)  with  printed  field  number. 


21 


For  study  skins  and  entire  specimens  in  fluid,  some  collectors  use  a  label  similar  to 
that  illustrated  in  Figure  9b.  Information  recorded  on  these  labels  includes  locality, 
date,  sex,  collector's  name,  identification  of  specimen,  measurements,  and 
reproductive  data.  Standard  measurements  (see  section  4.3)  are  always  listed  in  the 
following  sequence:  (1)  total  length;  (2)  tail  vertebrae  length;  (3)  hind  foot  length;  (4) 
ear  length;  and  in  bats  (5)  tragus  length,  and  (6)  forearm  length.  At  the  ROM  these 
labels  are  now  generated  by  our  computerized  cataloguing  system.  As  a  result,  we  do 
not  fill  out  these  labels  in  the  field  and  study  skins  and  fluid-preserved  specimens  are 
labelled  with  field  number  tags  (Fig.  9d). 

To  prepare  the  tag  for  tying,  run  a  thread  through  two  holes  near  one  end  of  the  tag 
and  tie  a  knot  about  2.5  cm  (1  inch)  from  the  tag  (Fig.  9a).  You  can  save 
considerable  time  in  the  field  by  stringing  your  tags  with  thread  before  you  take  them 
into  the  field. 

Tie  tags  on  study  skins  and  specimens  in  fluid  above  the  ankle  with  a  square  knot 
(Fig.  37).  For  flat  skins,  also  write  the  field  number  on  the  cardboard  stretcher  with 
waterproof  ink.  If  printed  field  tags  are  used,  they  should  be  tied  directly  to  the 
cardboard  (Fig.  41).  Some  collectors  (Anderson,  1965)  record  such  data  as  sex, 
measurements,  locality,  and  date  on  the  card.  For  "cased"  or  "open"  skins  from 
larger  mammals  that  are  to  be  tanned,  attach  the  field  number  through  the  nostrils. 

If  skulls  or  skeletons  are  stored  in  individual  gauze  bags  for  drying,  tie  a  tag  around 
the  neck  of  the  bag  (Fig.  39b).  If  skulls  or  skeletons  are  not  placed  in  individual  bags, 
attach  the  tag  directly  to  the  specimen.  Skull  labels  can  be  tied  around  the  mandible  or 
in  larger  mammals  to  the  zygomatic  arch.  A  suitable  area  for  tying  labels  to 
articulated  skeletons  is  the  pelvis.  For  disarticulated  skeletons,  label  each  portion 
with  a  tag.  If  large  skeletons  are  placed  in  burlap  bags,  you  can  also  attach  a  tag  to  the 
outside  of  the  bag. 


4.3     Measurements  and  Weights 

Mammalogists  rely  on  weights  and  body  measurements  for  aid  in  identifying 
specimens,  determining  the  age  of  specimens,  and  for  studying  variation  between 
different  populations.  It  is  essential  that  the  collector  record  accurate  measurements 
and  weights  before  the  specimen  is  prepared  as  a  study  skin  or  preserved  in  fluid. 
Study  skins  shrink  somewhat  during  their  preparation  and  reliable  measurements 
cannot  be  made  from  the  finished  skin.  Fluid-preserved  specimens  become  stiff  and 
inflexible  once  they  have  set  in  the  fixative  and  are  difficult  to  measure  accurately. 
Measurements  used  in  research  papers  and  descriptions  of  species  are  always  given  in 
metric  units.  Linear  measurements  should  be  in  millimetres  and  weights  in  grams  or 
kilograms.  Indicate  an  approximate  measurement  by  the  circa  abbreviation  "ca", 
e.g.,  ca  180  mm.  Also  note  any  aberrant  measurements  resulting  from  damaged 
specimens  (tail  broken,  ear  torn). 

Measurements 

The  following  are  the  standard  measurements  taken  by  North  American  collectors 
(Fig.  10).  European  collectors  frequently  record  head  and  body  length  (HB)  rather 
than  total  length  and  omit  the  claw  for  the  hind  foot  measurement.  For  the  sake  of 

22 


ws 


Fig.  10  Standard  body  measurements  for  bats.  Total  length  (TL),  forearm  length  (FA),  hind 
foot  length  (HF),  tragus  length  (TR),  ear  length  (E),  tail  vertebrae  length  (TV),  and 
wingspan  (WS).  For  other  small  mammals,  only  the  total  length,  tail  vertebrae,  hind 
foot,  and  ear  are  recorded. 


23 


consistency,  we  recommend  that  collectors  use  the  North  American  measurements. 

Total  Length  (TL):  straight-line  distance  from  the  tip  of  the  nose  to  the  end  of  the 
last  tail  vertebra,  exclusive  of  the  hairs.  Lay  the  mammal  on  its  back  on  the  ruler  and 
measure  by  extending  the  specimen,  pressing  the  body  flat.  Pull  the  tail  (if  present)  to 
its  full  length,  measuring  to  the  end  of  the  last  bone.  If  no  tail  is  present,  measure  to 
the  end  of  the  backbone. 

Tail  Vertebrae  (TV):  distance  from  the  base  of  the  tail  to  the  tip  of  the  last  vertebra, 
exclusive  of  the  hairs.  With  the  mammal  on  its  belly,  place  the  ruler  at  the  point 
where  the  tail  joins  the  body,  pull  the  tail  upward  and  measure  to  the  end  of  the  last 
vertebra. 

Hind  Foot  (HF):  distance  from  the  end  of  the  heel  bone  (calcaneum)  to  the  end  of 
the  claw  on  the  longest  toe.  Stretch  the  toes  and  measure  from  the  heel  to  the  longest 
length  of  the  claws.  For  hoofed  mammals,  the  HF  measurement  is  taken  from  the  tip 
of  the  hock  to  the  tip  of  the  hoof  (Fig.  1 1). 

Ear  Length  (E):  distance  from  the  base  of  the  notch  of  the  lower  part  of  the  ear  to 
the  uppermost  margin  of  the  ear. 

Measurements  limited  to  bats  are: 

Tragus  (TR):  distance  from  where  the  tragus  joins  the  ear  to  its  tip. 

Forearm  (FA):  distance  from  the  outside  of  the  wrist  to  the  outside  of  the  elbow. 
Fold  the  wing  when  taking  this  measurement. 

Wingspan  (WS):  distance  between  the  wing  tips  when  the  wing  is  stretched  out. 
Lay  the  bat  on  its  belly  and  gently  stretch  the  wings,  being  careful  not  to  overstretch 
them. 

Measure  large  mammals  on  level  ground  using  a  steel  tape  measure.  The  same 


Fig.    1 1     Standard  body  measurements  for  a  large  ungulate.  Total  length  (TL),  tail  length 
(TV),  hind  foot  (HF),  ear  from  notch  (E),  and  height  at  shoulder  (HS). 


24 


standard  measurements  (TL,  TV,  HF,  E)  are  taken  for  these  mammals  (Fig.  11).  An 
additional  measurement  is  the  height  of  the  shoulder  (HS)  which  is  the  distance  from 
the  top  of  the  shoulder  to  the  bottom  of  the  foot.  For  total  length,  measure  in  a  straight 
line  with  the  body  stretched  out  rather  than  measuring  around  the  curves  of  the  neck 
and  back. 

The   measurements  for  cetaceans  recommended  by   the  American   Society  of 
Mammalogists  are  shown  in  Figure  12. 

Weights 

Specimens  should  be  weighed  promptly  and  before  preparing.  Weights  should  be 
taken  in  grams  or  kilograms;  however,  body  weights  in  pounds  or  ounces  are  helpful 
when  metric  scales  are  not  available.  For  approximate  weights,  use  the  abbreviation 
"ca".   The  body  weight  of  a  large  mammal  is  difficult  to  obtain   in  the  field; 


Fig.  12  Standard  cetacean  measurements  as  recommended  by  the  American  Society  of 
Mammalogists.  LENGTH:  1  total,  2  tip  of  upper  jaw  to  centre  of  eye,  3  tip  of  upper 
jaw  to  apex  of  melon  boss,  4  gape,  5  tip  of  upper  jaw  to  external  auditory  meatus,  6 
centre  of  eye  to  external  auditory  meatus,  7  tip  of  upper  jaw  to  blowhole  along 
midline  or  to  midlength  of  two  blowholes,  8  tip  of  upper  jaw  to  anterior  insertion  of 
flipper,  9  tip  of  upper  jaw  to  tip  of  dorsal  fin,  10  tip  of  upper  jaw  to  midpoint  of 
umbilicus,  11  tip  of  upper  jaw  to  midpoint  of  genital  aperture,  12  tip  of  upper  jaw  to 
centre  of  anus,  13  anterior  insertion  of  flipper  to  tip,  14  axilla  to  tip  of  flipper,  15 
dorsal  fin  base,  16  distance  from  nearest  point  on  anterior  border  of  flukes  to  notch. 
WIDTH:  17  nipper  (maximum),  18  flukes  (tip  to  tip).  HEIGHT:  19  dorsal  fin  (fin  tip 
to  base).  GIRTH:  20  on  a  transverse  plane  intersecting  axilla,  21  maxima,  22  on  a 
transverse  plane  intersecting  the  anus. 


25 


nevertheless,  collectors  should  weigh  large  mammals  whenever  possible  because  of 
the  paucity  of  weight  data. 

High  quality  spring  balances  graduated  in  grams,  for  example,  Pesola  scales 
(Bleitz  Wildlife  Foundation,  5334  Hollywood  Boulevard,  Hollywood,  California, 
USA)  are  excellent  for  the  field  collector.  They  are  made  in  the  following  capacities: 
5  g,  10  g,  30  g,  100  g,  500  g,  1000  g,  and  2500  g.  An  Ohaus  triple  beam  balance 
(Fisher  Scientific  Company,  711  Forbes  Avenue,  Pittsburgh,  Pennsylvania,  USA) 
may  also  be  used  for  weighing  mammals  to  2000  g.  Although  more  accurate  than 
Pesola  balances,  the  triple  beam  balance  is  heavier  and  less  compact.  For  mammals 
greater  than  2500  g  use  a  heavy-duty  spring  balance  (Forestry  Supplier  Incorporated, 
Cox  8397/205  West  Rankin  Street,  Jackson,  Mississippi,  USA). 


4.4     Determining  the  Sex  of  Mammals 

The  sex  of  each  specimen  should  be  accurately  determined.  However,  if  there  is 
doubt,  so  indicate  in  your  Field  notes  or  catalogue. 

External  Genitalia 

The  external  genitalia  of  the  male  usually  can  be  distinguished  from  those  of  the 
female  by  larger  size  and  their  position  relative  to  the  anus.  Most  males  have  a 
prominent  penis  (Fig.  13),  but  some  small  mammals,  particularly  shrews,  have  the 
penis  retracted  into  a  sheath  of  a  tubular  fold  of  skin  during  the  intervals  between  the 
breeding  seasons.  Consequently,  the  external  genitalia  may  appear  to  be  superficially 
similar  in  both  sexes.  With  fine  pointed  forceps,  it  is  usually  possible  to  protrude  the 
penis  from  its  sheath.  A  hand  lens  is  often  useful  for  examining  the  genitalia  in  small 
mammals.  Many  species  have  a  bony  or  cartilaginous  structure  in  the  penis,  the 
baculum  (os  penis). 

In  most  adult  males,  the  testes  occur  outside  the  abdominal  cavity,  but  in  a  few 
mammals  (whales  and  dolphins)  the  testes  remain  permanently  within  the  abdominal 
cavity.  When  the  testes  occur  outside  the  abdomen,  they  are  usually  situated  in  a 
scrotum  (Fig.  13a).  Testes  may  remain  permanently  in  the  scrotum  (most  primates, 
dogs,  ungulates)  or  they  may  be  intra-abdominal  during  the  nonbreeding  season  (most 
bats,  some  rodents).  In  some  mammals  (shrews,  moles,  some  rodents,  hares),  the 
testes  are  not  contained  in  a  distinct  scrotum  and,  although  they  are  located  outside 
the  abdominal  cavity,  they  remain  under  the  integument  in  the  inguinal  region. 

The  external  genitalia  of  females  consist  of  a  vaginal  opening  (vulva)  that  may 
have  prominent  skin  folds  in  some  species.  The  urethra  may  also  be  visible  (Fig.  13 
C,D).  During  the  breeding  season,  teats  or  nipples  of  the  female  mammary  glands  may 
be  enlarged.  The  number  and  position  of  the  mammary  glands  vary  greatly  in 
different  species.  In  some  mammals  (primates  and  bats)  there  is  only  a  single  pair  of 
mammary  glands  confined  to  the  chest  region.  However,  in  mammals  with  numerous 
glands  (rodents)  the  teats  are  usually  situated  in  parallel  rows  along  the  ventral  surface 
of  the  chest  and  abdomen  (Fig.  13E). 

In  cetaceans  (whales,  dolphins,  and  porpoises),  the  genitalia  are  contained  in  a 
genital  groove  (Fig.  14).  Normally  the  penis  is  retracted  fully  into  a  pouch  in  the 
ventral  abdominal  wall  and  only  the  genital  slit  can  be  seen.  The  penis  protrudes  from 

26 


Fig.  13  External  genitalia  of  a  male  and  female  cricetid  rodent:  a  scrotum,  b  penis,  c  anus, 
d  teats,  e  vulva,  f  vaginal  opening  (perforate),  g  vaginal  opening  (imperforate), 
h  mammary  tissue  (stippled  area). 

A     An  adult  male  with  an  enlarged  scrotum  that  partially  obscures  the  anus. 
B     An  immature  male  without  an  enlarged  scrotum. 
C     Vulva,  anus,  and  a  perforate  vagina  on  a  pregnant  female. 
D     Schematic  drawing  of  a  female  showing  a  membrane  covering  the  vaginal 

opening  (imperforate  condition). 
E     Schematic  drawing  showing  the  position  of  mammary  tissue  under  the  teats. 

27 


Fig.    14     Schematic    drawing   to   show    the   external    genitalia   of   a   porpoise    (cetacean): 
a  umbilicus,  b  genital  slit,  c  mammary  slit,  d  anus,  e  penis. 
A     Female  porpoise  illustrating  the  presence  of  mammary  slits  and  the  position  of 

the  genital  slit. 
B     Male  porpoise  with  penis  retracted  into  abdomen.  Note  position  of  the  genital  slit 

relative  to  the  anus. 
C     Male  porpoise  with  penis  protruding  from  the  genital  slit. 


28 


the  genital  slit  only  during  erection  or  occasionally  on  death.  The  female  genitalia  are 
also  contained  in  a  genital  slit  but  the  distance  from  the  centre  of  the  genital  slit  to  the 
anus  is  much  less  in  females  than  in  males.  In  some  porpoises,  the  anal  and  genital 
openings  may  occupy  the  same  aperture.  A  number  of  accessory  grooves  may  flank 
the  female  genital  slit,  but  one  pair — the  mammary  slits  or  grooves  which  contain  the 
nipples — is  always  present  and  in  a  constant  position  in  all  species  of  cetaceans.  The 
mammary  slits  are  not  present  in  male  cetaceans. 

Internal  Reproductive  Organs 

After  the  skin  has  been  removed,  specimens  to  be  prepared  as  study  skins  or  skeletons 
should  be  dissected  to  verify  the  sex  and  to  obtain  reproductive  data  (see  section  4.5). 
Testes  appear  as  whitish  or  yellowish  oval  organs  (Fig.  15).  During  intervals  between 
the  breeding  season,  testes  may  be  small,  especially  in  small  mammals  (shrews). 
Females  can  be  distinguished  by  the  presence  of  a  uterus  (Fig.  16). 


Fig.  15  Schematic  drawing  of  the  male  urogenital  system  of  the  Norway  rat  {Rutins 
norvegicus)  as  an  example  of  a  typical  rodent:  a  kidney,  b  ureter,  c  prostate  gland, 
d  urinary  bladder,  e  vas  deferens,  f  testis,  g  cauda  epididymis,  h  penis. 


29 


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Fig.  16  Schematic  drawing  of  the  female  urogenital  system  of  the  Norway  rat  (Raitus 
norvegicus)  as  an  example  of  a  typical  rodent:  a  kidney,  b  ureter,  c  ovary,  d  uterus 
(left  horn),  e  urinary  bladder,  f  vagina,  g  urethra,  h  vaginal  orifice,  i  anus. 

4.5     Reproductive  Data 

Notes  on  the  condition  of  the  reproductive  organs  provide  important  biological  data. 
The  length  and  time  of  the  year  of  the  breeding  season,  litter  size,  numbers  of  litters 
per  year,  and  the  age  of  sexual  maturity  may  often  be  determined  for  a  particular 
species  in  a  given  geographic  area  from  these  data. 

Mammals  prepared  as  study  skins  or  skeletons  (sections  5.2  and  5.4)  should  be 
dissected  immediately  after  the  skin  is  removed.  Open  the  body  cavity  by  cutting  the 
abdominal  muscles  with  scissors  or  a  scalpel  and  examine  the  reproductive  organs. 
Fluid-preserved  specimens  (section  5.1)  are  usually  not  dissected  in  the  field; 
nevertheless,  important  information  on  the  breeding  condition  of  the  specimen  can  be 
provided  by  examining  the  external  genitalia.  If  the  condition  of  the  reproductive 
organs  cannot  be  determined  because  of  decomposition,  then  indicate  so  in  your  field 


30 


notes.  Do  not  guess  at  the  reproductive  status!  If  you  have  difficulty  distinguishing 
embryos  or  placental  scars  (see  page  32),  then  preserve  the  uterus  in  a  vial  of  10  per 
cent  buffered  neutral  formalin  (with  corresponding  field  number)  and  include  it  with 
your  collection  of  specimens. 

A.  Males 

Criteria  used  to  distinguish  breeding  males  are  the  size  of  the  testes  and  the  size  of  the 
tubules  in  the  cauda  epididymis.  For  dissected  specimens,  measure  the  length  and 
width  of  the  testes  (both  if  different  in  size)  in  millimetres  (e.g.,  10  mm  x  6  mm). 
For  fluid-preserved  specimens  that  have  a  scrotum  (section  4.4),  determine  whether 
or  not  the  testes  are  grossly  enlarged. 

Another  useful  criteria  for  breeding  males  in  various  small  species  (shrews, 
rodents,  bats)  is  the  occurrence  of  visible  tubules  in  the  cauda  epididymis  (Fig.  15).  If 
the  tubules  are  visible  to  the  eye,  they  are  swollen  and  usually  contain  sperm. 
However,  if  the  tubules  are  not  visible,  they  are  probably  void  of  sperm.  For 
dissected  specimens,  note  whether  or  not  the  tubules  are  visible  and  record  the 
condition  in  your  field  notes. 

B.  Females 

Breeding  females  may  be  pregnant,  lactating,  or  both.  Criteria  used  to  diagnose  the 
breeding  condition  of  females  are  the  condition  of  the  vagina,  presence  or  absence  of 
embryos,  presence  or  absence  of  placental  scars,  and  the  condition  of  mammary 
tissue. 

CONDITION  OF  THE  VAGINA 

The  vagina  of  females  is  usually  sealed  by  a  membrane  until  puberty.  In  some  rodents 
and  moles  (Talpidae)  that  breed  seasonally,  the  vagina  may  be  closed  by  a  membrane 
during  the  nonbreeding  (anoestrus)  of  the  reproductive  cycle  (Fig.  13d).  The  vagina 
in  this  condition  is  described  as  imperforate.  In  contrast,  during  heat  (oestrus),  the 
vagina  is  not  sealed  by  a  membrane  and  is  perforate  (Fig.  13c).  In  some  mammals, 
for  example  the  squirrels  (Sciuridae),  the  vaginal  region  (vulva)  may  appear  to  be 
swollen  or  turgid  during  oestrus.  The  condition  of  the  vagina  is  usually  a  reliable 
indication  of  reproductive  condition,  so  note  whether  the  vagina  is  imperforate  or 
perforate  and  also  whether  the  vulva  is  obviously  swollen. 

LACTATION 

Lactation  is  defined  as  the  secretion  of  milk.  The  following  criteria  are  used  as 
evidence  that  a  female  is  lactating:  (1)  female  is  observed  nursing  young;  (2)  milk  can 
be  squeezed  from  teats;  (3)  heavy  deposits  of  mammary  tissue  that  contain  milk  are 
present.  The  criterion  of  milk  in  the  mammary  tissue  can  be  only  applied  to  dissected 
specimens.  This  mammary  tissue  is  found  on  the  inside  of  the  skin  in  areas  under  the 
teats  (Fig.  13e)  and  is  usually  whitish  in  colour  and  may  spread  beneath  the  skin  some 
distance  from  the  teats.  Indicate  in  your  field  notes  the  presence  of  the  mammary 
tissue  and  whether  the  tissue  contains  milk. 


31 


PREGNANCY 

Pregnancy  is  defined  as  the  condition  of  having  a  developing  foetus  or  embryo. 
Females  in  late  pregnancy  may  have  a  swollen  abdomen  and  at  this  stage  it  may  be 
possible  to  detect  embryos  by  squeezing  or  pinching  the  abdomen. 

In  dissected  mammals,  carefully  examine  the  uterus.  When  examining  the  uterus, 
it  may  be  helpful  to  dissect  it  out  and  stretch  it  on  a  piece  of  white  board  or  paper.  For 
mammals  with  thick-walled  uteri,  you  may  have  to  open  the  uterus  to  examine  it  but 
this  is  seldom  necessary  for  shrews,  mice,  or  bats.  The  presence  of  embryos  is 
positive  evidence  of  pregnancy  (Fig.  17c).  Count  and  measure  the  crown-rump  length 
(CR)  of  all  embryos.  This  measurement  (Fig.  17d)  is  from  the  top  of  the  head  to  the 
end  of  the  rump  with  the  embryos  in  situ  (not  straightened).  If  more  than  one  embryo 
is  present,  measure  several  and  give  an  approximation  of  their  size  (e.g.,  5  embryos, 
CR  =  16  mm).  Some  collectors  make  it  standard  practice  to  denote  the  number  of 
embryos  in  the  right  (R)  and  left  (L)  horns  of  the  uterus  (e.g.,  5  embryos;  3L,  2R).  In 
mammals  having  more  than  one  embryo,  some  may  die  and  be  resorbed  into  the 
uterus.  Resorbed  embryos  appear  conspicuously  smaller  and  underdeveloped  when 
compared  with  normal  ones.  Be  careful  to  distinguish  any  resorbed  embryos  when 
recording  embryo  counts  (e.g.,  5  normal  embryos:  3L,  2R,  CR  =  15  mm;  2  resorbed 
embryos:  1L,  1R,  CR  =  3  mm).  Embryos  can  be  easily  preserved  by  placing  them  in 
a  vial  of  10  per  cent  neutralized  formalin.  If  embryological  studies  are  contemplated, 
preserve  in  Bouin's  solution  (see  section  6). 

The  uterus  should  also  be  examined  for  the  presence  of  placental  scars.  In  some 
mammals  (shrews,  rodents,  carnivores),  after  a  female  gives  birth  placental  scars 
form  at  sites  in  the  uterine  wall  where  embryos  were  implanted.  These  scars  appear  as 
yellow  to  black  pigmented  spots  on  the  inside  of  the  uterus  (Fig.  17b).  Although  the 
scars  become  increasingly  paler  and  smaller  with  age,  they  may  persist  to  one  year  in 
mice  and  rats.  Generally  the  number  of  scars  corresponds  to  the  number  of  embryos. 
However,  embryos  that  died  during  pregnancy  will  also  leave  scars  on  the  uterine 
wall  and  because  scars  from  several  litters  may  be  present,  the  number  of  scars  is  not 
always  an  accurate  indication  of  litter  size.  Nevertheless,  the  presence  or  absence  of 
placental  scars  is  important  to  determine  the  reproductive  history  of  the  animal.  If 
scars  are  readily  visible,  count  them  and  record  the  number  in  each  horn  of  the  uterus. 
Where  scars  are  badly  faded,  scars  from  several  litters  are  present,  or  when  scars  are 
obscured  by  embryos,  it  may  not  be  possible  to  count  them  accurately.  If  two  (or 
more)  sets  of  scars  representing  two  (or  more)  different  pregnancies  are  present,  one 
set  of  scars  will  appear  larger  than  the  others.  Although  it  may  be  impossible  to  count 
all  scars,  it  is  important  to  indicate  that  two  (or  more)  sets  of  scars  were  observed. 
Examples  of  placental  scar  data:  2  sets  of  placental  scars  present — not  counted;  4 
placental  scars  (3L,  1R);  no  placental  scars  present. 

With  the  data  obtained  from  examining  the  uterus,  females  can  be  classified  as 
follows:  nulliparous — no  embryos  or  placental  scars;  primiparous — embryos  or  one 
set  of  placental  scars;  multiparous — embryos  and  one  (or  more)  sets  of  placental  scars 
present,  or  two  (or  more)  sets  of  placental  scars  present. 


4.6     Locality  Descriptions 

Mammalogists  are  increasingly  concerned  with  studies  of  geographic  variation  and 

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variation  within  populations.  For  this  research  detailed  and  accurate  descriptions  of 
collecting  sites  are  required.  The  following  locality  data  are  required:  country,  state 
or  province,  county  or  equivalent,  township  or  equivalent,  local  area  or  equivalent 
(town,  lake  name,  name  of  nearby  mountain),  and  the  precise  latitude  and  longitude 
to  the  nearest  minute.  Unfortunately,  accurate  mapping  of  collecting  sites  is 
frequently  prohibited  by  insufficient  data  provided  by  collectors.  Examples  of 
problems  resulting  from  incomplete  and  inaccurate  locality  descriptions  are:  locality 
description  consisting  only  of  a  village  name  that  cannot  be  located  on  any  map, 
locality  description  consisting  of  the  name  of  a  town  or  village  (no  other  data)  when 
there  may  be  several  towns  of  the  same  name  in  the  country,  failing  to  distinguish 
between  road  distance  (speedometer  mileage)  and  map  or  airline  distance. 

To  avoid  such  problems,  please  follow  these  guidelines  for  documenting  your 
collecting  localities.  If  possible  give  the  state  or  province  and  the  county  (or 
equivalent  if  such  exists)  in  the  country.  This  is  helpful  in  limiting  the  search  for  a 
locality.  The  local  area  designation  (a  mountain,  lake,  river,  valley)  should  be  given 
when  it  is  a  prominent  feature.  To  locate  a  collecting  site  precisely,  give  map  or 
airline  distance  (miles  or  kilometres)  and  direction  from  a  permanent  reference  point 
and  latitude  and  longitude  to  the  nearest  minute  if  possible.  A  town  or  a  mountain 
peak  is  a  suitable  reference  point  if  it  appears  on  small-scale  maps  (e.g.,  1 :500  000). 
If  the  name  of  a  town  or  village  is  the  same  as  a  nearby  mountain,  river  or  lake,  insert 
the  word  town  in  parentheses,  for  example,  Rainy  River  (town).  Remember  that  a 
good  reference  point  must  be  readily  identifiable  now  as  well  as  any  time  in  the 
future.  Transitory  features  that  may  be  moved,  renamed,  or  eliminated  such  as 
wayside  taverns,  small  ponds,  roads,  highway  numbers  or  junctions,  and 
campgrounds  should  be  avoided.  Also  avoid  local  names  that  do  not  appear  on 
published  maps  for  they  may  be  impossible  to  locate.  Distance  from  the  reference 
points  should  be  given  in  map  or  airline  distances  and  not  in  road  distance  calculated 
from  a  speedometer.  Road  mileage  in  mountainous  terrain  is  extremely  inaccurate. 
Also,  new  road  construction  and  reroutings  make  highway  distances  transitory.  If 
road  mileage  is  used,  you  must  indicate  that  the  distance  is  road  mileage  and  not 
airline  distance. 

Finally,  we  urge  collectors  to  include  with  their  field  catalogues  and  field  notes 
large-scale  topographic  maps  (1 :50  000  or  1 :250  000)  with  collecting  sites  indicated. 
Maps  of  various  scales  for  Europe,  Asia,  Australia,  Latin  America,  Oceania,  and  the 
United  States  may  be  obtained  from  Defence  Mapping  Agency,  Department  of 
Defence,  Topographic  Center,  Washington,  DC  20315,  USA.  Topographic  maps  of 
Canada  and  an  index  listing  available  maps  may  be  obtained  from  Energy  Mines  and 
Resources  Canada,  Surveys  and  Mapping  Branch,  Canada  Map  Office,  615  Booth 
Street,  Ottawa,  K1A  0E9.  Topographic  sheets  for  the  Province  of  Ontario  may  be 
obtained  from  Ontario  Ministry  of  Natural  Resources,  Map  Office,  Queen's  Park, 
Toronto,  M7A  1W4. 


4.7     Habitat  Descriptions 

A  description  of  the  habitat  in  which  the  specimen  was  collected  gives  an  indication 
of  its  ecological  distribution.  Therefore,  provide  as  much  habitat  information  as 
feasible  for  all  specimens. 


34 


A  useful  habitat  description  includes:  (1)  an  indication  of  the  general  biome 
(desert,  arctic  tundra,  savannah,  coniferous  forest,  hardwood  forest,  alpine  tundra, 
rain  forest).  (2)  The  dominant  or  most  prevalent  types  of  plants  (palm  grove,  white 
spruce  and  balsam-fir  forest,  banana  plantation,  acacia  scrub  forest).  If  you  know  the 
scientific  names  of  plants,  use  them  in  the  description.  (3)  Note  the  elevation,  for 
example,  3000  m  above  sea  level  (ASL).  Elevation  can  be  accurately  estimated  from 
topographic  maps  or  with  a  pocket  altimeter.  For  calculations  from  maps,  use  the 
units  given  on  the  map  rather  than  converting  metres  to  feet  or  vice  versa.  (4)  Any 
pertinent  information  on  the  history  of  the  area  should  be  given  (area  burned  over  by 
forest  fire  in  1968;  area  cut  over  for  logging  in  1970).  (5)  Any  pertinent  information 
on  soil  type  or  geological  formations. 

Rare  mammals  that  are  seldom  captured  by  collectors  warrant  particularly  detailed 
descriptions  of  their  habitat.  Frequently  little,  if  anything,  is  known  about  the  ecology 
of  these  species.  For  bats,  describe  roosting  sites  or  netting  sites  (roosting  in  humid 
cave,  roosting  in  palm  tree,  netted  over  small  stream). 

Examples  of  informative  habitat  descriptions  are  as  follows:  trapped  in  alpine  zone, 
400  m  ASL,  vegetation  scrubby  willows  and  mosses;  netted  in  dense  mature  forest, 
1000  m  ASL;  from  a  large  colony  roosting  in  humid  limestone  cave,  near  banana 
plantation,  400  m  ASL;  trapped  in  treeless,  grassland  area  200  m  ASL;  trapped  in 
mature  jackpine  balsam-fir  forest.  Figure  7  illustrates  typical  habitat  data  recorded  in 
field  notes. 


4.8     Methods  of  Capture 

Describe  how  the  specimen  was  collected  (trapped,  shot,  netted,  found  dead,  road 
kill,  poisoned).  If  all  your  specimens  were  captured  in  the  same  manner,  then  write 
this  at  the  beginning  of  your  catalogue  or  field  notes  to  avoid  repetition. 


4.9     Miscellaneous  Field  Notes 

This  includes  any  miscellaneous  behavioural  or  ecological  observations  that  you  may 
have  made.  Although  these  observations  may  seem  to  be  trivial,  they  frequently 
prove  to  be  valuable  in  natural  history  studies.  Examples  are  as  follows:  netted  at 
08  00  h;  trapped  between  08  00  h  and  09  00  h;  unusual  colour  phase;  observed 
copulating  with  field  number  20;  specimen  is  young  of  field  number  17;  species 
observed  feeding  on  papaya  fruit;  males  and  females  roosting  in  different  parts  of  the 
cave;  tick  on  right  ear;  this  colony  of  bats  observed  flying  out  of  cave  at  18  00  h; 
many  of  this  species  occupying  the  same  burrow.  Also  record  observations  on 
climatic  conditions  in  your  field  notes.  Weather  conditions  may  influence  small 
mammal  trapping  or  the  netting  of  bats.  Examples  of  these  observations  are:  rainy 
season,  dry  season,  heavy  rains  during  trapping  period. 


4.10     Photographic  Records 

Colour  slides  or  black  and  white  photographs  of  specimens  and  collecting  sites  are  a 
useful  way  to  supplement  documentation  data.  Photographs  of  rare  mammals  that  are 

35 


seldom  captured  by  collectors  or  aberrant  specimens  (e.g.,  unusual  colour  phases) 
may  prove  invaluable,  particularly  if  these  specimens  represent  species  new  to 
science.  Close-up  photographs  of  the  facial  regions  of  live  mammals  taken  in  mist 
nets  or  live  traps  are  an  excellent  way  to  illustrate  the  structure  and  colour  of  fleshy 
appendages  (e.g.,  bat  nose-leaves)  that  may  fade  or  shrink  in  study  skins  or 
fluid-preserved  material.  You  may  also  wish  to  photograph  mammals  that  are 
prepared  as  complete  skeletons  without  skins  in  order  to  make  a  permanent  record  of 
pelage.  Photographs  of  carcasses  of  beached  whales  and  dolphins  prepared  as  skeletal 
material  are  also  valuable.  You  will  enhance  your  habitat  descriptions  (section  4.7) 
with  photographs  of  the  vegetation  on  trap  lines  or  at  bat  netting  sites.  Photographs 
may  be  the  only  way  to  document  rare  or  endangered  species  protected  by  law. 

Most  field  biologists  prefer  the  35  mm  single-lens  reflex  camera  because  of  its 
light  weight  and  versatility.  Various  accessories  (bellows,  extension  tubes, 
macrolenses)  are  made  for  close-up  work.  The  authors  have  found  a  wide-angle  lens 
(35  mm  or  28  mm  focal  length)  ideal  for  habitat  photographs. 


5.     Methods  for  Preparing  Specimens 


Three  kinds  of  museum  specimens  are  usually  prepared  from  mammals:  skins  with 
accompanying  skulls  and/or  partial  skeletons,  complete  skeletons,  and  entire 
mammals  preserved  in  fluid.  Each  of  these  has  advantages  and  disadvantages  and  the 
kind  of  specimen  prepared  depends  on  the  objectives  of  the  collector.  Ideally,  a 
representative  series  of  a  species  from  a  given  locality  should  contain  all  three  types 
of  specimens.  Study  skins  are  essential  for  analysing  pelage  colour  and  moult 
patterns;  fluid-preserved  specimens  are  valuable  for  studying  anatomy  and  histology. 
Skeletons  are  useful  for  studies  in  comparative  anatomy,  geographic  variation,  and 
determining  age  but  skeletons  of  many  species  are  poorly  represented  in  collections. 
Collectors  are  encouraged  to  prepare  complete  skeletons  (at  least  one  male  and  one 
female)  for  each  species  collected  when  feasible. 

The  condition  of  the  specimen  will  often  determine  the  kind  of  specimen  that 
should  be  prepared.  For  preserving  in  fluid,  live  mammals  from  mist  nets  or  live  traps 
are  most  suitable.  Keep  mammals  alive  in  collecting  bags  or  cages  until  they  are  to  be 
prepared.  Mammals  from  snap  traps  or  specimens  that  have  been  frozen  can  usually 
be  prepared  as  study  skins.  Mammals  from  snap  traps  should  be  prepared  as  quickly 
as  possible  because  they  decompose  rapidly.  Once  the  skin  of  a  mammal  begins  to 
"slip"  (fur  falling  out),  it  is  difficult  to  salvage  a  satisfactory  study  skin  from  it. 
Decomposed  specimens  in  which  the  internal  organs  have  deteriorated  and  the  fur  is 
slipping  are  best  prepared  as  skeletons.  A  "skull  only"  should  be  salvaged  if  the 
remaining  carcass  is  badly  damaged. 


5.1     Preserving  in  Fluid 

Because  changes  in  tissues  occur  shortly  after  death,  specimens  should  be  preserved 
immediately  after  killing.  To  effectively  kill  small  mammals  (bats  and  mice)  without 


36 


damaging  the  skin  and  skull,  use  an  airtight  jar,  can,  or  plastic  bag  with  a  wad  of 
cotton  containing  a  few  drops  of  chloroform  or  ether.  Avoid  inhaling  these  chemicals 
as  they  are  toxic  to  humans.  Ether  and  chloroform  are  also  highly  inflammable. 
Larger  mammals  (hares,  foxes)  can  be  humanely  and  quickly  killed  by  injecting  them 
in  the  heart  region  with  Euthanyl  (sodium  pentobarbital).  The  recommended  dosage 
is  1  ml  per  2.3  kg  (5  lb.)  body  weight.  Used  by  veterinarians,  Euthanyl  is  a  restricted 
drug  that  can  only  be  obtained  by  prescription.  You  may  find  it  necessary  to  calm 
large  mammals  with  ether  or  chloroform  before  injecting  them. 

The  preparation  of  entire  mammals  in  fluid  involves  two  steps:  fixing  the  tissues  of 
the  specimen  with  a  solution  such  as  10  per  cent  formalin,  Bouin's  solution,  or 
sodium  acetate  and  transferring  the  specimen  for  permanent  storage  to  a  preserving 
fluid,  for  example,  65  to  70  per  cent  ethanol  or  45  to  60  per  cent  isopropyl  alcohol. 
"Fixing"  halts  enzyme  processes  in  tissues  and  hardens  or  "sets"  the  specimen. 
Preservatives  prevent  the  growth  of  microrganisms  and  also  prevent  gradual  chemical 
or  physical  changes  in  the  specimen's  structure. 

Unless  specimens  are  to  be  stored  for  two  months  or  longer  before  shipment,  the 
collector  need  be  concerned  only  with  fixation.  Fluid-preserved  specimens  received 
from  field  collectors  are  washed  for  12  to  24  h  in  water  and  then  transferred  to  65  per 
cent  ethanol  for  permanent  storage  in  museum  collections.  The  best  fixative  for  the 
field  collector  is  a  solution  of  10  per  cent  buffered  neutral  formalin.  Formalin  is  a 
solution  of  formaldehyde.  The  commercially  available  formalin  is  usually  a  37  per 
cent  (weight/weight)  or  40  per  cent  (weight/volume)  solution  of  formaldehyde.  These 
commercial  formaldehyde  solutions  are  treated  as  100  per  cent  formalin;  therefore,  to 
produce  a  10  per  cent  formalin  solution,  mix  one  part  40  per  cent  formaldehyde  with 
nine  parts  water.  To  reduce  volume,  most  collectors  carry  full  strength  (40%) 
formaldehyde  solutions  in  the  field  and  dilute  them  to  10  per  cent  formalin  before 
preserving  their  specimens.  A  wide-mouthed  glass  jar  or  a  plastic  pail  makes  a 
convenient  container  in  which  to  dilute  formaldehyde  and  to  fix  specimens.  Because 
formalin  solutions  are  usually  acidic  (pH  3.0  to  4.6),  they  tend  to  decalcify  teeth  and 
excessively  harden  tissue.  To  neutralize  acidity,  add  a  teaspoon  of  powdered  borax 
(sodium  tetraborate)  or  a  tablespoon  of  household  ammonia  to  1  gal.  (3.8  L)  of  10 
per  cent  formalin.  Best  results  are  obtained  by  using  a  precise  mixture  of  salts  to 
buffer  the  formalin  to  neutrality  (pH  7.0).  For  example,  a  mixture  of  4  g  of  acid  or 
monobasic  sodium  phosphate  monohydrate  (NaH2P04H20)  and  6.5  g  of  dibasic 
sodium  phosphate  anhydrate  (Na2HP04)  will  buffer  1  L  of  10  per  cent  formalin. 
About  40  g  of  this  salt  mixture  neutralizes  1  gal.  (3.8  L).  This  dry,  salt  mixture  can  be 
prepared  in  advance  and  carried  into  the  field  in  plastic  bags.  Other  equipment  for 
preserving  specimens  includes  a  hypodermic  syringe  and  hypodermic  needles  for 
injecting  the  body  cavity  and  larger  muscles.  If  injection  equipment  is  not  available, 
mammals  can  be  preserved  by  making  a  slit  in  the  abdomen  to  open  the  body  cavity  to 
allow  the  formalin  to  enter. 

After  specimens  have  been  killed,  weighed,  measured,  and  assigned  a  number  (see 
section  4),  a  field  tag  should  be  tied  securely  to  each.  If  you  use  paper  labels,  be 
certain  that  they  will  not  disintegrate  in  the  preserving  fluid.  Using  waterproof  ink  or 
a  pencil,  write  the  number  and  sex  symbol  (  ?  for  female  and  a*  for  male)  on  both 
sides  of  the  label. 

Once  properly  tagged,  lay  the  mammal  on  its  back  and,  with  the  syringe  full  of 
formalin,  insert  the  needle  into  the  abdomen  and  slowly  fill  the  body  cavity  until  it 


37 


becomes  turgid.  Do  not  inject  too  much  fluid,  but  be  sure  that  the  body  cavity  is  full 
and  firm.  For  large  mammals  insert  the  needle  into  the  larger  muscles  and  inject  a 
small  amount  of  the  formalin.  For  mammals  with  fleshy  tails  (rats)  slit  the  tail  with 
several  cuts  using  a  scalpel  or  sharp  knife. 

After  injection,  the  specimen  is  fixed  by  placing  it  in  ajar,  pan,  or  pail  containing 
10  per  cent  buffered  neutral  formalin.  Care  should  be  used  to  keep  the  specimen  in  a 
normal,  relaxed  position  for  it  will  retain  this  shape  permanently  once  it  has  been 
fixed.  If  the  mouth  is  not  locked  tight,  prop  it  open  with  a  small  piece  of  wood  or  a 
piece  of  cotton  before  the  specimen  is  fixed.  This  permits  examination  of  the  teeth  for 
identification  without  damaging  the  mouth  parts.  For  bats,  wings  should  be  partially 
closed  in  a  natural  position.  Usually  the  wings  are  in  satisfactory  shape  if  the  bat  is 
killed  in  a  relaxed  position.  Do  not  overcrowd  specimens  in  a  container  before  they 
are  thoroughly  fixed  (usually  12-48  h).  Two  factors  are  important:  (1)  to  keep  the 
specimen  in  a  natural  undistorted  position;  (2)  to  make  certain  there  is  sufficient 
volume  of  formalin  to  properly  fix  the  specimen.  A  safe  rule  is  to  have  sufficient 
formalin  to  completely  cover  the  specimens. 

After  12  to  48  h  specimens  are  fixed  and  they  may  be  packed  more  tightly  in 
containers  for  storage.  Avoid  using  metal  containers  (unless  acid-proof  lined)  as 
formalin  causes  almost  immediate  rust  and  corrosion  that  will  discolour  specimens.  If 
only  metal  lids  are  available,  a  waxed,  cardboard  liner  will  seal  the  container  for  only 
a  short  time  because  of  corrosion.  Therefore,  place  a  piece  of  waxed  paper  or  a  sheet 
of  plastic  over  the  mouth  of  the  jar  before  screwing  on  the  lid.  If  specimens  are  to  be 
stored  for  a  long  period  before  shipment  (more  than  8  weeks),  they  should  first  be 
washed  thoroughly  in  fresh  water  and  then  placed  in  65  to  70  per  cent  ethanol  or  45  to 
60  per  cent  isopropyl  alcohol. 


5.2     Preparing  Skins 

Three  types  of  skins  can  be  prepared  for  museum  specimens:  (1)  Traditional  study 
skins  that  are  filled  with  cotton  or  a  similar  material  to  approximate  the  natural  shape 
of  the  mammal.  As  the  leg  bones  are  ordinarily  left  in  the  skin,  a  complete  skeleton 
cannot  be  obtained  and  usually  only  the  skull  is  kept.  (2)  Flat  skins,  which  consist  of 
the  skin  stretched  over  a  cardboard  outline.  For  a  flat  skin,  it  is  possible  to  obtain  a 
skull  and  most  of  the  skeleton.  (3)  Tanned  skins,  which  are  first  dried  and  later  tanned 
for  permanent  preservation.  A  skull  and  skeleton  can  be  obtained  from  a  mammal 
prepared  as  a  tanned  skin  with  only  the  terminal  digits  left  on  the  skin. 

The  choice  of  skin  depends  on  the  size  of  mammal  and  the  collector's  objectives. 
Small  mammals  (bats,  rodents,  insectivores)  are  prepared  as  study  or  flat  skins.  The 
study  skin  has  been  traditionally  used  by  museum  collectors.  This  type  of  skin  may  be 
more  time-consuming  to  prepare,  especially  for  the  inexperienced,  but  it  is  invaluable 
for  studying  pelage.  Flat  skins  have  the  advantage  of  being  quick  and  easy  to  prepare 
and  they  provide  both  a  skull  and  a  skeleton.  However,  flat  skins  are  difficult  to 
compare  with  study  skins  when  analysing  pelage.  Skins  from  mammals  larger  than  a 
fox  are  too  bulky  to  be  made  into  study  or  flat  skins  on  cardboard  and  must  be 
prepared  as  tanned  skins.  Study  skins  can  be  prepared  for  small  fur-bearing  mammals 
up  to  the  size  of  a  fox,  however,  some  collectors  prefer  to  make  tanned  skins  for  these 
mammals. 


38 


A.     Study  Skins 

Begin  with  a  midventral  incision  from  the  level  of  the  last  rib  to  near  the  anus  (Fig. 
18).  Always  cut  to  one  side  of  the  penis  or  vagina  so  that  the  external  genitalia  remain 
attached  to  the  skin.  To  keep  the  skin  clean  and  dry,  cornmeal,  borax,  magnesium 
carbonate  powder,  or  sawdust  may  be  sprinkled  on  the  skin  or  placed  in  a  skinning 
tray  or  pan  to  absorb  blood  and  body  fluids.  Another  skinning  technique  is  to  make  an 
incision  that  extends  across  the  lower  abdomen  and  down  the  inside  of  the  leg  to  the 
heels  (Fig.  18).  Leave  the  external  genitalia  on  the  skin  by  cutting  between  the  anus 
and  genitalia.  For  males  that  have  a  baculum  in  the  penis,  be  careful  not  to  cut  or 
damage  this  structure  for  it  may  be  an  important  aid  in  identification.  With  mammals 
such  as  bats  or  mice,  the  baculum  can  be  left  intact  in  the  penis  to  dry  on  the  skin.  If 
bacula  studies  are  anticipated,  remove  the  entire  penis  and  store  it  in  100  per  cent 
glycerine,  10  per  cent  formalin,  or  70  per  cent  alcohol.  For  larger  mammals,  the 
baculum  should  be  extracted  from  the  penis,  tagged  and  dried  with  the  skull  and  any 
skeletal  material. 

With  fingertips,  a  scalpel  handle,  or  blunt  forceps,  work  the  skin  free  of  the  body 
wall  in  the  vicinity  of  the  incision.  Try  not  to  cut  into  the  body  cavity.  Holding  the 
hind  foot,  push  the  knee  joint  upward  towards  the  midline  of  the  body.  Peel  the  skin 
off  the  leg  to  the  ankle,  then  sever  the  hind  leg  at  the  hip  or  knee  joint  with  scissors  or 
a  scalpel  (Fig.  19).  When  the  hind  legs  are  free,  work  the  skin  to  the  base  of  the  tail. 
Use  care  while  skinning  around  the  anus  and  the  anal  scent  glands  found  in  some 
mustelids  (Mustelidae). 

If  the  mammal  has  a  nonfleshy  tail  (e.g.,  some  bats),  cut  it  close  to  the  trunk  and 
leave  the  tail  vertebrae  in  the  skin.  If  a  fleshy  tail  is  present,  slip  it  out  of  the  skin  and 
later  replace  it  with  a  wrapped  wire.  Rolling  the  tail  on  a  table  top  or  skinning  board 
will  help  loosen  the  connective  tissue  that  attaches  the  tail  vertebrae  to  the  tail  sheath. 
For  shrews,  mice,  and  other  small  specimens  grasp  the  tail  at  the  base  of  the  sheath 
with  the  thumb  and  index  finger  (Fig.  20)  of  one  hand.  Press  the  thumb-  and 
finger-nails  firmly  against  the  tail  vertebrae.  Then  with  the  other  hand,  slowly  pull  the 
tail  vertebrae  until  they  are  free  of  the  skin.  If  the  tail  vertebrae  break  off  in  the  tail 
sheath,  you  must  split  the  skin  of  the  tail  and  remove  the  vertebrae.  After  inserting  a 
tail  wire,  the  incision  should  be  sewn  with  a  fine  needle  and  thread.  For  larger 
mammals,  it  may  be  necessary  to  hold  the  base  of  the  tail  sheath  with  heavy  forceps 
or  two  blocks  of  wood.  For  mammals  larger  than  a  squirrel,  it  is  usually  necessary  to 
split  the  tail  by  a  longitudinal  incision  in  order  to  remove  the  vertebrae. 

With  the  tail  free,  the  skin  can  now  be  peeled  back  to  the  region  of  the  front  legs 
(Fig.  21).  Do  not  pull  the  skin  off  the  body,  as  this  will  result  in  an  overstretched 
study  skin.  A  recommended  method  is  to  use  one  hand  to  gently  push  the  skin  off  the 
body  and  with  the  scalpel  held  in  the  other  hand,  sever  any  connective  tissue  holding 
the  skin  to  the  carcass.  Remove  the  skin  from  the  front  legs  down  to  the  ankle.  For 
bats,  detach  the  skin  as  far  as  the  elbow  joint.  With  scissors  or  a  scalpel,  cut  the  front 
legs  (or  wing  bones  of  bats)  at  the  shoulder  joint  (Fig.  22).  Peel  the  skin  over  the  chest 
area  to  the  base  of  the  skull. 

Probably  the  most  difficult  stage  of  the  skinning  operation  is  to  remove  the  skin 
from  the  head  region  without  damaging  the  ears,  eyelids,  lips,  and  skull.  Use  a  sharp 
scalpel  for  skinning  the  head  region.  Carefully  work  the  skin  over  the  head  until  you 
reach  the  cartilaginous  bases  of  the  ears  (Fig.  23).  Pick  away  any  fatty  tissue  that  may 


39 


WmmM :  r  i 


Fig.    18     Initial  incision  is  made  midventrally  (dashed  line)  or  across  the  heels  (solid  line). 


40 


^^)^ 


WW nl 


1 

:  Ms* 


Fig.    19     Severing  the  hind  leg  at  the  knee  joint. 


41 


Fig.  20     Removing  tail  vertebrae  from  the  tail  sheath. 


obscure  the  ear  cartilage  and  sever  the  cartilage  at  the  base  of  the  ear.  Continue  to  peel 
the  skin  over  the  head  until  the  eyes  are  exposed.  With  the  skin  held  away  from  the 
head,  cut  the  membrane  that  covers  the  eyes  (Fig.  24).  The  skin  should  be  still 
attached  in  the  eye  region  at  the  front  corner  of  the  eyelid.  Carefully  cut  this 
attachment  with  your  scalpel  but  avoid  cutting  into  the  eyelid,  as  the  skin  of  the  eye 
region  will  tear  when  the  skin  is  stuffed.  Work  the  skin  to  the  lips  and  sever  the 
connective  tissue  that  attaches  the  lips  to  the  skull.  Finally,  peel  the  skin  forward  until 
it  is  attached  to  the  body  only  at  the  tip  of  the  nose.  Cut  the  nasal  cartilage  being 
careful  not  to  cut  into  the  nasal  bones  of  the  skull  (Fig.  25). 

Once  the  skin  is  removed,  dissect  the  carcass  for  reproductive  data  (section  4.5) 
then  direct  your  attention  to  the  skin.  Remove  all  fat  and  excess  flesh  from  the  skin. 
To  accelerate  drying  and  inhibit  insect  damage,  rub  a  drying  agent  into  the  flesh  side 
of  the  skin.  At  the  ROM,  we  use  magnesium  carbonate  powder  for  study  skins  and  flat 
skins.  This  powder  is  available  from  most  biological  or  chemical  supply  companies. 
Borax  can  also  be  used  as  a  drying  agent-preservative.  However,  there  is  some 
evidence  that  borax  may  affect  red-coloured  pelage;  therefore,  try  to  keep  borax 
powder  off  the  fur.  Arsenic,  arsenic  and  borax,  arsenic  and  alum,  alum  and  potassium 
nitrate,  and  arsenic  soap  have  been  used  in  the  past  as  drying-preserving  agents. 
Because  alum  may  affect  fur  colour  and  arsenic  is  toxic,  these  chemicals  are  not 


42 


Fig.   21     Skin  being  peeled  off  the  carcass. 


43 


Fig.  22     Location  of  cut  for  severing  the  front  legs. 


Fig.  23     Cutting  the  cartilage  at  the  base  of  ears. 


44 


Fig.   24     Skinning  around  the  eye. 


Fig.  25     Removing  the  skin  from  the  nose. 


45 


recommended  and  they  should  only  be  used  if  magnesium  carbonate  or  borax  is  not 
available. 

For  smaller  mammals  (mice,  shrews,  and  bats),  fat  and  flesh  can  be  picked  off  the 
skin  with  your  fingers;  however,  it  may  be  necessary  to  use  a  dull  knife  to  remove  this 
material  from  skins  of  larger  mammals.  A  simple  method  for  degreasing  skins  that 
have  heavy  fat  deposits  is  to  dip  them  in  naphtha  or  white  gas.  Shake  off  any  excess 
gas  and  roll  the  skin  in  sawdust  to  hasten  drying.  Do  not  wring  the  skin  as  this  will 
stretch  it.  A  liberal  dusting  of  fur  with  magnesium  carbonate  or  sawdust  before  and 
during  skinning  usually  prevents  blood  from  adhering  to  the  skin.  Heavily  matted 
blood  around  wounds  may  be  removed  with  water  or  alcohol  on  a  cotton  wad, 
followed  by  dusting  with  magnesium  carbonate  or  sawdust. 

Remove  the  muscle  tissue  from  the  leg  or  wing  bones  with  scissors,  scalpel,  or 
forceps  (Fig.  26)  and  rub  the  bones  in  magnesium  carbonate.  Restore  the  legs  to  their 
approximate  original  shape  by  wrapping  the  bones  with  cotton  to  replace  the  muscles. 
With  the  skin  still  reversed,  sew  the  lips  together  (Fig.  27). 


Fig.   26     Removing  muscle  tissue  from  the  leg  bone. 


46 


Fig.   27     Stitch  used  to  close  the  lips. 


Now  the  skin  is  ready  to  fill  with  a  body  and  head  made  from  a  single  piece  of 
cotton.  Some  collectors  prefer  to  use  fine  tow  rather  than  cotton.  Roll  the  cotton  into  a 
smooth  cylindrical  bundle  that  is  slightly  longer  and  thicker  than  the  body  of  the 
mammal  (Fig.  28).  Form  the  head  region  of  the  cotton  filler  with  a  pair  of  forceps  by 
pressing  in  the  centre  at  the  end  of  the  roll  (Fig.  29).  Grasp  the  two  corners  on  either 
side  of  the  forceps,  fold  together,  and  take  a  new  hold  of  the  pointed  end  and  shape  as 
a  smooth  cone  (Fig.  30). 

Place  the  cone  into  the  head  of  the  skin  and  reverse  the  skin  over  the  points  of  the 
forceps  (Figs.  31,  32).  Adjust  the  eyes,  ears,  and  mouth,  then  continue  to  reverse  the 
skin  slowly  over  the  cotton  until  the  specimen  is  completely  filled.  The  length  of  the 
cotton  body  can  be  trimmed  with  scissors  to  fill  the  skin  properly  (Fig.  33).  For  study 
skins  of  small  species  of  bats,  mice,  and  shrews,  some  collectors  prefer  to  construct  a 
separate  head  rather  than  use  a  single  piece  of  filling.  Best  results  are  obtained  by 
constructing  the  head  from  fine  tow  and  wrapping  it  with  a  thin  wisp  of  cotton.  Use 
the  skull  as  a  guide  for  size.  Instead  of  sewing,  hold  the  lips  in  position  by  inserting 
small  pins  into  the  tow.  After  the  head  is  shaped,  fill  the  body  with  a  single  piece  of 
cotton. 

If  the  tail  vertebrae  were  removed,  then  an  appropriately  sized  wire  wrapped  with 
cotton  must  be  inserted  into  the  tail  for  support  (Fig.  34).  The  collector  will  require 
the  following  gauges  of  wire  for  preparing  skins:  12  gauge  (hares),  16  gauge  (large 
squirrels),  18  and  20  gauge  (small  squirrels),  22  and  24  gauge  (mice,  rats,  shrews), 
26  gauge  (small  shrews  and  small  bats).  If  available,  use  Monel  wire  as  it  does  not 
corrode.  Cut  the  wire  to  a  length  that  extends  from  the  tip  of  the  tail  to  midway  into 
the  body.  A  loop  at  the  body  end  of  the  wire  provides  added  strength  and  stability  to 
the  finished  specimen.  Wrap  thin  wisps  of  cotton  to  form  a  shape  similar  to  that  of  the 
original  tail  vertebrae  (Fig.  35).  It  may  be  necessary  to  moisten  the  tail  wire  with 
saliva  to  make  the  cotton  adhere.  Species  with  long  tails  that  taper  to  a  fine  tip 
(jumping  mice),  present  a  problem  because  the  tail  tip  is  too  narrow  to  accommodate 
the  usual  tail  wire.  A  very  thin  wire  (26  gauge)  can  be  tapered  to  a  fine  point  with  a 
file.  However,  a  better  method  is  to  prepare  tapered  wires  in  advance  of  fieldwork  by 
dipping  precut  wires  into  an  acid  solution  to  form  a  long,  tapering  point  that  will  fit 
the  tail  sheath.  Dipping  Monel  wire  for  5  min  in  a  solution  of  one  part  hydrochloric 
acid  (HCL)  and  two  parts  nitric  acid  (HNO3)  will  effectively  produce  a  tapering 
point.  Oxide  deposits  on  the  wire  can  be  removed  by  placing  wires  for  several 
minutes  in  an  enamel  tray  containing  hydrochloric  acid.  Pad  the  portion  of  the  looped 

47 


Fig.  28     Rolling  cotton  into  a  cylindrical  bundle. 


Fig.   29     Grasping  the  cotton  with  forceps. 
48 


Fig.   30     Forming  the  head  with  fingers  and  forceps. 


tail  wire  that  extends  beyond  the  tail  into  the  body  cavity  with  a  thin  piece  of  cotton 
then  stitch  the  midventral  incision  with  a  fine  needle  and  thread  (Fig.  36)  and  tie  a 
field  tag  (see  section  4.2)  to  the  hind  foot  of  the  skin. 

The  next  step  is  to  anchor  the  study  skin  to  a  pinning  board  (cardboard,  corkboard, 
Styrofoam,  or  wallboard)  for  drying.  Careful  pinning  is  the  key  to  a  well-prepared 
skin.  For  most  mammals  the  front  and  hind  feet  are  positioned  parallel  to  the  body 
and  held  in  place  with  pins  through  each  foot  and  a  pair  of  pins  at  the  outer  side  of 
each  hind  foot  near  the  heel  (Fig.  37).  Anchor  the  tail  by  a  pair  angled  across  its  base 
and  by  one  pair  angled  across  the  tip.  To  shape  the  ears  and  head,  use  pins  placed 
against  the  side  of  the  skin. 

Check  to  be  sure  the  head  is  symmetrical  and,  if  necessary,  a  thin  (insect)  pin  may 
be  used  to  anchor  it  in  place.  The  eyelids  may  be  held  open  by  pulling  through  a  small 
bit  of  cotton  from  the  head.  A  final  check  of  the  specimen  should  be  followed  by 
cleaning  the  fur  with  a  small  brush  (a  toothbrush  works  well)  to  remove  dirt  or  dust 
(Fig.  38). 

A  recommended  method  of  pinning  bat  wings  (Fig.  39a)  is  to  place  a  sharp  pin 
(insect  pins  are  preferable,  but  any  sharp  pin  will  do)  in  the  wing  joint  near  the  thumb. 
Position  the  wing  so  that  the  forearm  is  nearly  parallel  to  the  body  and  the  upper  arm 
joins  the  body  in  a  natural  position  at  a  slight  angle.  Some  of  the  membrane  above  the 
forearm  and  upper  arm  should  be  exposed,  but  the  wings  should  not  be  overstretched. 
The  second  pair  of  pins  is  inserted  at  the  elbow  to  hold  the  forearm  in  the  desired 


49 


Fig.   31     Cotton  body  is  inserted  into  the  head  region. 


Fig.   32     Skin  is  reversed  over  the  cotton. 


50 


Fig.  33     Cutting  the  cotton  to  the  appropriate  size. 


Fig.   34     Wrapping  the  tail  wire  with  cotton 


Fig.   35     Inserting  the  wrapped  wire  into  the  tail  sheath. 


Fig.  36     Stitch  used  to  close  the  body  incision. 


Fig.   37     Skin  is  pinned  out  for  drying  and  a  field  tag  is  attached  to  hind  foot. 


52 


Fig.   38     Brushing  the  fur  with  a  small  brush. 


position.  A  third  pair  of  pins  may  be  required  to  hold  the  end  of  the  upper  arm  in  the 
appropriate  position  close  to  the  body.  Pin  each  foot,  pulling  the  body  into  the  desired 
position.  If  a  tail  is  present,  extend  and  anchor  it  with  a  pin  at  the  tip  and  with  crossed 
pins  over  the  base  of  the  tail  near  the  body.  If  a  membrane  is  present  between  the  tail 
and  legs,  extend  and  anchor  it  by  placing  pins  near  the  end  of  the  calcar  (the 
cartilaginous  structure  extending  along  the  edge  of  the  membrane  from  the  heel  of  the 
foot).  The  wing  bones  are  then  pinned  so  that  each  digit  or  finger  is  spread  slightly 
away  from  adjoining  ones. 

The  pinned  specimen  must  be  dried  thoroughly  before  shipping  or  transporting. 
Drying  time  will  vary  considerably  with  local  conditions.  In  hot  dry  climates,  stuffed 
skins  may  dry  in  one  day;  however,  in  humid  climates  it  may  be  extremely  difficult  to 
dry  skins  completely.  A  shaded  area  with  good  air  circulation  provides  the  best 


53 


B 


Fig.  39     A     Dorsal  view  of  a  bat  study  skin  pinned  for  drying. 

B     Corresponding  skull  is  shown  in  a  gauze  bag  with  field  number  attached. 


conditions.  Do  not  place  skins  in  direct  sunlight  as  this  fades  pelage  and  intense  heat 
may  cause  excessive  shrinking  of  skins.  Under  poor  drying  conditions,  it  may  be 
necessary  to  unpin  specimens  and  to  expose  their  undersurface  to  the  air  by  turning 
them  upside  down.  Take  care  not  to  bend  or  break  the  ears  when  doing  so.  When 
skins  are  dried,  remove  the  pins  and  store  them  in  chests  or  shipping  boxes  (see 
section  7). 

Ants  and  egg-laying  flies  can  cause  extensive  damage  to  skins  and  most  collectors 
protect  their  drying  skins  by  storing  them  in  special  wooden  cases  that  have  screened 
openings  for  ventilation.  A  properly  screened  drying  chest  should  be  part  of  your 
standard  field  equipment;  however,  a  temporary  drying  container  can  be  constructed 
in  the  field  using  a  few  pieces  of  wood  and  cheesecloth.  At  the  ROM  we  use  wooden 
drying  chests  (90  cm  x  50  cm  x  35  cm;  35  inches  x  20  inches  x  14  inches),  that 
contain  80  cm  x  42  cm  (32  inches  x  17  inches)  sheets  of  2.5  cm  (1  inch)  Styrofoam. 
The  sheets  of  Styrofoam  are  separated  by  2.5  cm  (1  inch)  high,  wooden  frame 
spacers.  For  small  mammals  (shrews,  mice),  a  single  spacer  is  sufficient  for 
separating  Styrofoam  sheets,  for  larger  mammals  (hares),  two  or  three  spacers  are 
required.  Study  skins  are  pinned  to  the  Styrofoam  for  drying.  When  they  are 
sufficiently  dried,  pins  are  removed  and  each  layer  of  skins  is  covered  with  cotton. 

B.     Flat  Skins 

Flat  skins  mounted  on  cardboard  can  be  prepared  for  such  species  as  shrews,  mice, 
squirrels,   and  small   carnivores.    Many   collectors   use  the  method  described   by 


54 


Anderson  (1965)  where  both  front  and  hind  feet  are  left  on  the  skin.  We  recommend 
the  following  procedure  because  it  enables  the  collector  the  obtain  both  a  flat  skin  and 
a  skeleton  from  the  specimen.  The  skeleton  is  complete  except  for  the  one  front  and 
one  hind  foot  that  are  left  on  the  skin. 

Rather  than  making  a  cut  along  the  midline  of  the  abdomen,  begin  the  cut  at  one 
heel,  cutting  through  the  skin  at  the  back  and  inner  side  of  the  leg,  across  the  base  of 
the  tail  between  the  anus  and  external  genitalia,  and  then  extend  the  incision  to  the 
opposite  heel  (Fig.  18).  Leave  the  external  genitalia  on  the  skin.  Detach  the  skin  from 
the  legs  and  cut  through  the  leg  bone  at  the  ankle  of  only  one  leg;  leave  that  foot  on 
the  skin.  On  the  opposite  leg,  detach  the  skin  to  the  ankle  and  then  cut  the  skin  there. 
This  foot  is  left  attached  to  the  body  of  the  mammal  as  part  of  the  skeleton.  Now 
remove  the  skin  from  the  tail  and  pull  it  towards  the  front  legs.  Do  the  same  for  the 
front  legs  as  the  hind  legs — leave  one  foot  on  the  body  of  the  mammal  and  detach  the 
other  foot  with  the  skin.  Remove  the  skin  from  the  head  region  being  careful  not  to 
damage  the  ears  or  lips.  Dissect  the  carcass  for  reproductive  data  (section  4.5).  Clean 
all  fat  and  excess  flesh  from  the  skin  and,  to  hasten  drying,  rub  a  drying  agent  (borax, 
magnesium  carbonate)  into  the  flesh  side  of  the  skin  (see  section  5.2A). 

Unlike  the  conventional  study  skin,  the  flat  skin  is  stretched  on  a  piece  of 
cardboard  or  corrugated  pasteboard.  To  prepare  the  stretcher,  lay  the  skin  flat  on  the 
board  and  trace  its  outline.  Shape  the  card  with  scissors,  leaving  a  sufficient  amount 
of  the  card  behind  the  shaped  outline  to  support  the  tail  and  to  permit  writing  of  field 
data  (Fig.  40).  Use  a  board  sufficiently  thick  to  support  the  skin  fully.  Cardboard 
sheets  of  different  thicknesses  should  be  carried  into  the  field  by  collectors  who 
intend  to  prepare  flat  skins.  Pull  the  skin  over  the  stretcher  board,  being  careful  not  to 
overstretch.  For  small  mammals,  the  skin  is  put  on  the  board,  fur  side  out,  but  for 
mammals  larger  than  a  squirrel,  the  skin  should  be  stretched  on  the  board  flesh  side 
out  for  a  few  days.  Then,  after  the  skin  has  partly  dried,  reverse  it  and  pull  it  on  to  the 
board,  fur  side  out. 

Insert  a  wrapped  tail  wire  for  support  as  with  conventional  study  skins  (see  section 
5.2A)  and  tie  the  hind  foot  and  base  of  the  tail  to  the  board  with  thread  (Fig.  41).  You 
will  need  heavy  sail-makers'  needles  for  piercing  heavy  cardboard.  Small  pins  are 
used  for  holding  the  front  foot  in  position  for  drying  and  for  shaping  the  lips  if 
necessary.  Use  a  toothbrush  for  a  final  cleaning  of  the  fur.  Tie  the  field  number  (see 
section  4.2)  to  the  stretcher  card  and  write  the  field  number  on  the  card  in  case  the  tag 
is  lost  (Fig.  41). 

A  modified  flat  skin  is  used  by  museum  collectors  for  hares  and  rabbits  (Fig.  42). 
Because  the  hind  legs  are  supported  on  a  wooden  stick,  this  type  of  skin  is  sturdier 
than  the  conventional  study  skin.  Also  it  requires  less  space  for  storage.  A  heavy 
stretcher  (corrugated  cardboard)  is  cut  to  fit  the  skin.  A  wooden  stick  which  extends 
from  the  head  to  beyond  the  hind  feet  is  attached  to  the  board  by  means  of  cord  or 
wire.  Wrap  the  cardboard  stretcher  with  a  thin  layer  (0.5  cm;  0.25  inches)  of  cotton 
and  insert  it  into  the  skin.  It  may  be  necessary  to  trim  the  posterior  end  of  the  board 
with  shears  to  fit  the  skin  properly.  Wires  should  be  inserted  in  each  leg  to  provide 
support.  Secure  the  hind  legs  to  the  stick  with  wire  or  heavy  thread;  the  front  legs  are 
positioned  parallel  to  the  head.  The  ears  can  be  held  together  flat  against  the  skin  in  a 
natural  position  with  a  single  stitch  of  thread.  Sew  the  skinning  incision  and  tie  a  field 
number  to  one  hind  leg.  At  the  ROM,  we  are  using  a  modified  version  of  this  method 
for  our  hare  skins.  The  skin  is  prepared  in  the  same  manner  as  the  traditional  hare  flat 


55 


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skin  except  that  only  one  hind  foot  and  one  front  foot  are  left  on  the  skin.  The  other 
feet  are  left  on  the  carcass  as  part  of  the  skeleton. 

Flat  skins  dry  quickly  and  under  optimum  conditions  they  may  be  sufficiently  dried 
in  24  h.  Follow  the  precautions  for  drying  study  skins,  that  is,  keep  flat  skins  out  of 
direct  sunlight  and  protect  them  from  insect  pests.  After  they  have  been  dried,  flat 
skins  can  be  packed  compactly  into  boxes  for  shipping. 

C.    Skins  to  be  Tanned 

Mammal  skins  larger  than  a  fox  must  be  prepared  for  tanning,  although  smaller 
fur-bearing  mammals  (foxes,  ermine,  beaver)  may  also  be  prepared  for  tanning. 
Skinning  pelts  for  tanning  may  be  either  "cased"  or  "open".  Pelts  from  fur-bearers 
other  than  beaver  are  usually  prepared  "cased"  by  professional  trappers;  however, 
the  choice  of  skinning  method  is  really  a  question  of  personal  preference.  Large 
mammals  such  as  bears,  deer,  moose,  and  seals  should  be  skinned  "open".  For  a 
discussion  of  techniques  for  mammals  that  require  special  treatment,  see  Anderson 
(1965). 

"Cased"  skins  are  removed  from  the  mammal  in  much  the  same  manner  as  the  flat 
skin  (see  section  5.2B).  Make  an  incision  from  foot  pad  to  foot  pad  along  the  hind 
legs.  Detach  the  skin  from  the  hind  legs  to  the  foot.  The  skin  can  be  separated  from 
the  carcass  by  pushing  down  with  thumb  and  fingers  between  the  skin  and  carcass. 
Skin  out  the  feet  leaving  only  the  claws  on  the  skin  and  remove  the  tail  vertebrae  from 
the  tail  sheath.  For  mammals  larger  than  a  squirrel,  split  open  the  tail  on  the  ventral 
side.  With  the  tail  vertebrae  free,  pull  the  skin  down  the  carcass  to  the  front  legs. 
Detach  the  skin  from  the  front  legs,  leaving  the  claws  on  the  skin,  then  pull  the  skin 
over  the  head  region.  Carefully  skin  around  the  ears,  eyes,  mouth,  and  nose. 

Cased  skins  should  be  stretched,  fur  side  in,  over  a  frame  for  drying.  For  the 
collector  who  prepares  the  occasional  pelt,  a  stretcher  can  be  improvised  from  soft 
wood,  wire,  or  corrugated  cardboard.  However,  if  you  plan  to  collect  a  number  of 


Fig.  41     Example  of  a  flat  skin  prepared  from  a  chipmunk  (Sciuridae). 


57 


Fig.  42  Modified  flat  skin  used  for  hares.  Hind  feet  are  tied  to  a  stick  which  is  attached  to  a 
cardboard  outline  covered  with  a  thin  layer  of  cotton:  a  leg  wires,  b  cardboard 
outline,  c  wooden  stick. 


fur-bearers,  then  you  should  make  a  drying  board  for  the  various  species  that  you 
intend  to  collect.  Drying  boards  approved  by  the  fur  trade  for  different  species  are 
available  commercially  (Southeastern  Outdoor  Supplies,  Route  3,  Box  503,  Bassett, 
Virginia,  USA).  Adhesive-backed  templates  in  various  standard  sizes  and  shapes  are 
also  sold  commercially.  The  template  is  placed  on  a  board  which  is  then  cut  to  the 
appropriate  size  and  shape. 

For  "open"  skins  begin  with  a  midventral  incision  from  the  throat  extending 
posteriorly  to  the  tip  of  the  tail,  being  careful  to  cut  to  one  side  of  the  genitalia  (Fig. 
43a).  Cuts  are  then  made  from  this  midventral  incision  along  the  inside  of  each  leg  to 
the  foot.  Usually  the  claws  or  hoofs  are  left  on  the  skin;  however,  if  the  carcass  is  to 


58 


Fig.  43     Cuts  for  skinning  a  large  mammal. 
A     Ventral  view  of  cuts. 

B     Enlarged  view  of  cuts  for  skinning  leg  and  hoof, 
c     Cuts  for  skinning  around  antlers. 


be  prepared  as  a  skeleton,  then  leave  only  one  hind  foot  and  one  front  foot  on  the 
skin — the  other  feet  remain  on  the  carcass.  The  skin  of  some  mammals  (deer  and 
caribou)  can  be  pulled  off  easily  by  hand,  but  for  other  mammals  (bears),  the  skin 
must  be  removed  by  careful  cutting.  Figure  43c  illustrates  the  cuts  that  should  be 
made  for  skinning  around  horns  or  antlers. 

Once  the  skin  is  off,  remove  as  much  flesh  and  fat  as  possible  and  sponge  off  any 
blood  from  the  fur.  Be  extremely  careful  when  defleshing.  If  too  much  of  the  skin  is 
removed,  the  fur  will  fall  out  when  the  pelt  is  tanned.  An  ordinary  dull  table  knife 
makes  a  good  fleshing  tool.  Spread  a  layer  of  salt  (sodium  chloride)  evenly  on  the 
entire  flesh  side  of  the  skin  and  rub  it  in  thoroughly  with  the  hands.  Stretch  the  skin 
out,  flesh  side  exposed,  and  allow  it  to  dry  for  about  24  h  (longer  in  humid 
conditions).  Cheesecloth  or  mosquito  netting  can  be  used  to  keep  egg-laying  flies  off 
the  skin.  After  24  h,  shake  off  any  water  and  excess  salt.  Resalt  the  skin,  then  fold  the 
head  and  legs  in  and  roll  the  skin  into  a  bundle.  The  skin  should  be  periodically 
checked  for  signs  of  decomposition  and  the  presence  of  fly  eggs  or  larvae  and  it  may 
be  necessary  to  apply  another  treatment  of  salt.  The  skin  must  be  dried  as  thoroughly 
as  possible  prior  to  shipment  or  transport.  After  the  skin  is  received  from  the 
collector,  museums  usually  send  it  to  a  commercial  tanner  for  tanning.  It  is  important 


59 


not  to  treat  the  skin  with  chemical  preservatives  other  than  salt  in  the  field  as  these 
may  interfere  with  the  tanning  process. 


5.3     Preparing  Skulls 

As  soon  as  the  study  skin  is  prepared,  direct  your  attention  to  the  skull.  Care  should 
be  taken  to  prevent  damage  to  any  part  of  the  skull.  Separate  the  skull  from  the 
carcass  by  severing  at  the  joint  of  the  skull  and  the  first  vertebra  (atlas).  Fragile  skulls 
from  small  mammals  (shrews,  mice,  small  bats)  are  dried  without  any  cleaning. 
However,  the  brain,  eyes,  tongue,  and  heavy  muscle  layers  should  be  removed  from 
skulls  about  the  size  of  squirrels  or  larger.  A  piece  of  wire  with  a  small  hook  on  the 
end  can  be  used  to  pick  the  brain  tissue  out  of  the  cranium,  or  the  brain  tissue  can  be 
flushed  out  of  the  skull  with  a  syringe.  Cut  the  muscles  attaching  the  eyes  and  tongue 
with  scissors  and  then  pull  these  organs  from  the  skull  using  forceps.  Heavy  muscle 
tissue  can  be  removed  by  using  a  scalpel  or  scissors,  but  be  extremely  careful  not  to 
damage  the  thin  processes  on  the  skull.  For  skulls  with  antlers  in  velvet  (deer,  moose, 
etc.),  it  may  be  necessary  to  split  the  velvet  with  a  knife  to  facilitate  drying. 

Thoroughly  dry  skulls  in  the  field.  An  efficient  technique  for  drying  skulls  is  to 
place  them  in  cloth  bags.  Gauze  skull  bags  are  usually  supplied  to  ROM  collectors; 
however,  if  you  do  not  have  these  bags,  similar  ones  can  be  constructed  from 
cheesecloth  or  other  porous  material.  Write  the  field  number  in  pencil  on  a  heavy 
paper  or  cardboard  tag  and  tie  it  to  the  skull.  The  same  number  can  be  attached  to  the 
outside  of  the  bag  (Fig.  39b).  Skull  bags  can  be  strung  on  a  wire  and  put  out  in  a 
ventilated  place  to  dry.  Ensure  that  skulls  cannot  be  reached  by  animals  that  might  be 
attracted  to  them.  When  using  a  vehicle  in  the  field,  an  excellent  technique  for  drying 
skulls  is  to  tie  wire  strings  of  skulls  securely  under  the  hood  where  the  heat  of  the 
engine  and  air  flow  during  travelling  quickly  dries  them.  It  may  be  necessary  to  store 
skulls  inside  the  vehicle  at  night  to  protect  them  from  such  predators  as  racoons  or 
cats.  After  skulls  have  completely  dried,  they  can  be  compactly  packed  for  shipping. 
As  with  study  skins,  the  time  required  to  dry  skulls  varies  with  climatic  conditions. 
Before  packing,  ascertain  that  there  is  a  skull  for  every  skin  and  note  in  your 
catalogue  any  damaged  skulls. 


5.4     Preparing  Skeletons 

If  the  specimen  is  to  be  prepared  as  a  flat  skin  or  tanned  skin,  then  remove  the  skin  by 
the  methods  described  in  section  5.2.  However,  if  the  mammal  is  decomposed  with 
the  fur  slipping,  remove  and  discard  the  skin  in  the  quickest  manner  possible,  being 
careful  not  to  damage  the  skeleton.  Because  wing  membranes  must  be  removed  from 
the  bones  of  the  hand,  bats  prepared  as  skeletons  should  be  skinned  as  follows. 
Detach  the  skin  from  the  legs  as  far  as  the  ankle,  then  cut  the  skin  with  scissors  at  the 
ankle  joint.  Peel  the  skin  from  the  carcass  until  you  reach  the  wings.  Detach  the  skin 
from  the  arm  of  the  bat;  then  by  slowly  pulling  towards  the  wing  tips,  peel  the  wing 
membrane  off  the  wing  bones,  being  careful  not  to  break  the  delicate  bones.  Remove 
the  skin  from  the  head  region  in  the  usual  manner  (see  section  5.2). 

60 


When  the  skin  is  off  the  carcass,  dissect  for  reproductive  data  (see  section  4.5), 
then  extract  all  internal  organs  from  the  body  cavity.  Any  organs  left  in  the  carcass 
will  decompose  rapidly.  Next,  remove  the  larger  muscle  tissues  from  the  bones.  The 
amount  of  defleshing  required  depends  on  the  size  of  the  mammal.  To  avoid 
damaging  the  delicate  skeletons  of  such  small  mammals  as  shrews,  mice,  or  small 
bats,  do  not  attempt  to  cut  off  the  small  amount  of  flesh.  Simply  leave  the  skull 
attached  to  the  skeleton  and  allow  the  entire  carcass  to  dry.  For  medium-sized 
mammals  (squirrels,  hares,  fruit  bats,  small  carnivores),  remove  the  muscles  with 
scissors  and  forceps.  Although  it  is  not  necessary  to  disarticulate  the  skeleton  for 
these  mammals,  that  is,  to  cut  the  ligaments  that  hold  the  bones  together,  you  must 
separate  the  skull  from  the  skeleton  and  extract  the  brain,  tongue,  and  eyes  (see 
section  5.3).  Considerable  work  is  involved  in  defleshing  the  skeletons  of  large 
mammals  (deer,  bears,  seals)  and  a  sharp  skinning  knife  is  essential  for  cutting  the 
heavy  muscles  and  ligaments.  You  must  at  least  partially  disarticulate  large  mammals 
in  order  to  reduce  the  skeleton  to  manageable  sections.  Separate  the  skull  and  remove 
the  brain,  tongue,  and  eyes  (see  section  5.3). 

After  defleshing,  skeletons  must  be  dried  thoroughly  before  shipping  or 
transporting.  The  best  method  for  drying  skeletons  of  small-  to  medium-sized 
mammals  is  to  place  them  in  gauze  bags  that  protect  them  from  egg-laying  flies  but 
provide  ventilation  for  rapid  drying.  If  you  do  not  have  these  bags,  make  them  from 
cheesecloth  or  similar  material.  Tie  a  field  number  to  the  skeleton  and  place  a  single 
skeleton  in  each  bag.  For  bats  tie  the  wing  bones  against  the  body  to  prevent  them 
from  breaking  off.  After  tying  the  top  of  the  bag  tightly  with  string,  hang  it  to  dry 
following  the  precautions  described  for  drying  skulls  (see  section  5.3).  Burlap  bags 
make  excellent  drying  bags  for  skeletons  of  large  mammals.  Each  bag  should  have 
the  field  number  securely  attached.  Two  important  rules  to  follow  when  preparing 
skeletons  are:  (1)  do  not  place  skeletons  in  plastic  bags,  as  they  will  decompose 
instead  of  drying;  (2)  do  not  treat  skeletons  with  any  chemicals  as  they  will  inhibit  the 
activity  of  dermestid  beetles  that  are  used  in  many  museums  to  clean  skeletons. 


6.     Special  Techniques 


6.1     Karyotyping 

Slides  of  somatic  chromosomes  can  be  prepared  in  the  field  using  the  in  vivo  bone 
marrow  technique.  The  method  is  simple,  quick,  and  produces  slides  of  good  quality 
for  conventional  staining.  Most  workers  use  chromosomes  from  tissue  culture  for 
banding  studies. 

A  large  metal  toolbox  is  invaluable  for  carrying  karyotyping  equipment  in  the  field 
(see  Appendix  2).  Sodium  citrate  solutions  will  support  growth  by  bacteria  and 
consequently  must  be  prepared  fresh  each  day.  Weighing  and  separating  the  required 
daily  quantities  of  sodium  citrate  crystals  before  a  field  trip  saves  considerable  time. 
Small  vials  or  plastic  bags  are  suitable  containers  for  sodium  citrate.  Although  slides 
can  be  stained  in  the  field,  staining  solutions  add  considerable  bulk  and  weight  to  the 

61 


karyotyping  kit.  Slides  can  be  stained  with  good  results  1  to  2  months  after 
preparation  in  the  field.  Most  hand  centrifuges  hold  four  centrifuge  tubes;  therefore 
one  can  process  four  specimens  at  a  time.  Although  the  volume  of  suspension  in 
centrifuge  tubes  could  produce  a  dozen  or  more  slides,  we  generally  prepare  four  to 
six  slides  for  each  specimen. 

Practise  the  procedure  in  the  laboratory  before  attempting  to  do  it  in  the  field.  This 
will  enable  you  to  become  familiar  with  the  various  steps  and  to  verify  the  quality  of 
results. 

Mammals  that  have  been  karyotyped  must  be  kept  as  voucher  specimens  (study 
skins  or  preserved  in  fluid),  for  chromosome  slides  without  voucher  specimens  are 
virtually  worthless. 

The  following  technique  modified  from  Baker  (1970)  has  been  used  by  ROM  staff 
to  karyotype  bats,  small  rodents,  and  small  carnivores  in  the  field.  A  list  of  equipment 
required  for  karyotyping  is  given  in  Appendix  2. 

1.  Dilute  one  or  more  vials  (10  mg)  of  Velbe  (Eli  Lilly  &  Company,  Indianapolis, 
Indiana,  USA)  with  distilled  water  to  produce  a  0.025  per  cent  solution.  One  method 
is  to  take  a  serum  bottle  containing  100  ml  of  bacteriostatic  sodium  chloride  (Abbott 
Laboratories,  Montreal,  Canada)  and  remove  and  discard  20  ml  of  sodium  chloride 
solution  with  a  sterile  syringe.  Dissolve  the  contents  of  two  10  mg  vials  in  the  serum 
bottle  to  produce  an  80  ml  stock  solution  of  Velbe.  Keep  this  refrigerated.  For  a 
working  solution,  transfer  10  ml  of  stock  solution  to  any  empty  Velbe  container.  If 
working  with  colchicine,  use  a  0.04  per  cent  solution. 

2.  With  a  1  ml  tuberculin  syringe,  inject  the  mammal  intraperitoneally.  The  dosage 
of  Velbe  is  1  unit  (0.01  ml)  per  gram  of  body  weight.  Use  the  same  dosage  with 
colchicine.  After  injection,  the  mammals  must  be  kept  alive  for  1.5  to  2  h.  Bats  can 
be  kept  in  individual  collecting  bags;  rodents  or  carnivores  in  cages. 

3.  After  1.5  to  2  h,  anaesthetize  the  mammal,  dissect  out  the  humerus  (bats)  or  the 
femur  (rodents,  carnivores)  being  careful  not  to  damage  the  proximal  end.  Remove 
muscle  tissue  from  the  bone. 

4.  Using  a  5  ml  Luer  Lock  syringe,  flush  out  bone  marrow  with  3  ml  of  1  per  cent 
sodium  citrate  solution  (made  fresh  daily).  The  size  of  the  syringe  needle  will  depend 
on  the  size  of  the  bone.  Generally,  no.  21,  24,  or  26  needles  are  required  for  small 
mammals. 

5.  Vigorously  break  up  and  suspend  cells  with  a  pipette.  Then  let  the  solution  stand 
for  5  to  20  min  (more  than  20  min  may  rupture  cells). 

6.  Centrifuge  at  500  to  1500  rev/min  for  2  to  4  min. 

7.  With  a  pipette  remove  and  discard  the  supernatant  fluid  being  careful  not  to 
disturb  the  clump  of  cells. 

8.  Slowly  add  one  pipette  of  Carnoy's  fixative  (three  parts  absolute  methanohone 
part  glacial  acetic  acid)  to  the  centrifuge  tube.  By  carefully  adding  the  fixative  down 
the  inside  of  the  tube  with  a  pipette,  you  do  not  disturb  the  clump  of  cells.  With  the  tip 
of  the  pipette  close  to  but  not  touching  the  cells,  carefully  extract  the  fixative.  Add 
fresh  fixative,  suspend  the  cells  and  let  stand  for  10  to  12  min. 

9.  Centrifuge  for  2  to  4  min,  discard  supernatant,  then  resuspend  the  cells  in  fixative. 

10.  Repeat  this  procedure  two  or  three  times. 


62 


11.  After  the  final  centrif ligation,  resuspend  the  cells  in  fixative. 

12.  With  a  pipette,  place  two  or  three  drops  of  suspension  on  a  clean  microscope 
slide.  Ignite  by  quickly  passing  a  match  over  the  slide.  Do  not  touch  the  slide  with  the 
match.  Some  workers  prefer  to  air  dry  slides.  Use  microscope  slides  with  frosted  ends 
and  record  the  field  number  of  the  specimen  on  the  slide  with  a  lead  or  diamond 
pencil. 

13.  Slides  can  now  be  stained  in  the  field  or  sealed  in  a  slide  box  and  later  stained  in 
the  laboratory.  To  prepare  the  stain,  mix  eight  parts  of  warm  distilled  water  with  one 
part  Giemsa  stain  (filter  the  Giemsa  before  mixing  with  water).  Slides  are  stained  for 
13  min  in  a  Coplan  jar.  About  50  ml  of  stain  are  required  to  fill  a  Coplan  jar.  The 
destaining  process  requires  five  steps  in  Coplan  jars:  (1)  rinse  in  acetone;  (2)  1  min  in 
acetone;  (3)  1  min  in  acetone  xylol  (1:1);  (4)  1  min  in  xylol;  (5)  2  min  in  xylol. 
Mount  cover  slips  using  permount  while  slides  are  still  wet  with  xylol. 

If  slides  are  not  stained  immediately,  store  them  in  slide  boxes.  It  is  important  in 
the  field  to  keep  slides  dry  and  free  from  dust.  Place  a  small  packet  of  silica  gel 
crystals  in  each  box  and  tape  the  sides  of  the  box  to  make  it  airtight.  Store  slide  boxes 
in  plastic  bags. 


6.2     Collecting  Parasites 

Mammals  are  usually  hosts  of  many  parasites.  Those  found  externally  on  the  body  are 
ectoparasites;  parasites  found  in  internal  organs  are  referred  to  as  endoparasites. 

Ectoparasites 

Ectoparasites  are  insects  (parasitic  flies,  fly  larvae,  lice,  and  fleas)  or  arachnids  (mites 
and  ticks)  that  feed  on  the  body  fluids,  dead  skin,  tissues,  or  hair  of  the  host  mammal. 
In  bats  usual  parasites  are  bat  flies  and  mites,  whereas  lice,  mites,  ticks,  and  fleas  are 
commoner  on  rodents  and  other  mammals.  Although  many  techniques  exist  to  obtain 
ectoparasites,  the  following  is  a  simple  method  suitable  for  field  use.  If  the  mammal 
is  alive,  put  it  in  a  clean  plastic  or  cloth  bag  with  a  piece  of  cotton  soaked  in 
chloroform  or  ether  to  kill  the  ectoparasites  and  the  host.  Shake  the  dead  mammal  and 
the  inverted  bag  over  a  white  porcelain  tray  or  a  piece  of  white  paper  and  recover  the 
parasites  which  will  be  conspicuously  dark  on  the  white  background.  A  vigorous 
brushing  of  the  fur  with  a  toothbrush  will  remove  any  ectoparasites  that  are  caught  in 
the  fur.  Because  ticks  imbed  in  the  skin,  they  are  difficult  to  remove  from  the  host 
without  damaging  the  mouth  parts.  For  fluid-preserved  specimens,  leave  ticks  in 
position  on  the  mammal  and  make  a  note  on  your  data  sheets  that  these  ectoparasites 
are  present.  For  study  skins  detach  the  ticks  by  snipping  away  some  of  the  skin  of  the 
host  in  which  it  is  imbedded. 

There  are  several  precautions  to  follow  when  collecting  ectoparasites.  It  is  essential 
to  separate  different  species  of  mammals  in  collecting  bags.  If  different  species  of 
mammals  are  put  in  the  same  collecting  bag,  then  host  data  will  be  meaningless,  for 
most  ectoparasites  may  move  from  one  mammal  to  another  in  the  bag.  Handle 
ectoparasites  carefully,   as  legs,   wings,   and  other  body  parts  are  delicate.   Use 


63 


jeweller's  forceps  or  fine-tipped  brushes  moistened  in  alcohol  to  pick  up 
ectoparasites.  Ensure  that  instruments,  killing  bags,  and  pans  are  washed  and  clean 
before  processing  a  new  specimen. 

Preserve  all  ectoparasites  in  small,  screw-cap  or  rubber-stoppered  vials  with  70  per 
cent  ethanol  (do  not  use  formalin,  as  it  hardens  specimens).  Write  the  field  number  of 
the  host  and  any  other  pertinent  data  (e.g.,  site  on  body  of  host)  in  waterproof  ink  or 
pencil  on  sturdy  paper  and  place  it  in  the  vial.  Note  on  your  catalogue  sheets  or  field 
notebook  that  ectoparasites  were  preserved  for  that  particular  specimen.  If  you  wish 
further  information  on  parasites,  refer  to  the  appropriate  publications  listed  in  the 
bibliography. 


Endoparasites 

Endoparasites  most  frequently  found  in  mammals  are  helminth  worms  (trematodes, 
cestodes,  and  nematodes).  Trematodes  or  flukes  are  small,  flattened  worms  that  occur 
in  the  digestive  tract,  liver,  lungs,  and  other  internal  organs.  Cestodes  or  tape  worms 
are  long,  many-segmented  worms  that  live  in  the  intestine  of  the  host;  nematodes  or 
round  worms  are  unsegmented  worms  found  in  most  organs,  including  muscles.  It  is 
beyond  the  scope  of  this  manual  to  describe  the  many  special  techniques  for 
preserving  endoparasites.  But  for  the  field  collector  who  may  occasionally  find  these 
endoparasites  and  wishes  to  preserve  them  for  identification,  we  recommend  that  they 
be  stored  in  70  percent  alcohol.  A  small  amount  of  glycerine  (5  ml  in  100  ml  of  70% 
ethanol)  will  keep  parasites  pliable  and  reduce  hardening  of  tissues.  Label  vials  with 
the  field  number  of  the  host  and  note  in  the  catalogue  or  field  notebook  that  parasites 
were  preserved.  For  descriptions  of  special  methods  for  preserving  endoparasites, 
consult  references  given  in  the  bibliography. 


6.3     Tissues  for  Biochemical  Study 

Fresh  tissues  from  various  organs  (heart,  kidney,  liver,  ovary,  testes,  and  muscle)  can 
be  preserved  in  the  field  by  quick  freezing. 

Remove  the  desired  organs  from  freshly  killed  specimens.  Cut  a  5  to  10  mm  cube 
of  tissue  from  the  organ  with  scissors  or  a  scalpel  and  wash  in  physiological  saline  to 
remove  contaminating  blood.  The  saline  solution  should  be  prepared  fresh  each  day 
and  each  tissue  sample  should  be  rinsed  separately.  Ideally  the  tissue  should  be 
quick-frozen  in  liquid  nitrogen,  wrapped  in  aluminium  foil  and  stored  in  dry  ice. 
Label  each  sample  with  a  field  number  and  code  (e.g.,  H  for  heart,  K  for  kidney). 
Liquid  nitrogen  is  suitable  for  working  at  a  field  station  facility  but  may  be 
impractical  and  dangerous  to  use  in  other  field  situations.  If  liquid  nitrogen  cannot  be 
used,  wrap  tissues  in  foil,  label,  and  immediately  store  in  dry  ice.  A  small  Styrofoam 
cooler  with  a  tightly  fitting  lid  makes  an  ideal  dry  ice  chamber  (Sudia  et  al.,  1970). 
Tissue  samples  will  keep  for  three  days  in  such  a  container  with  dry  ice  without 
deterioration.  Storage  time  may  be  increased  by  replenishing  the  dry  ice  every  two 
days.  Once  samples  are  brought  to  the  laboratory,  they  can  be  stored  in  a  freezer  at 
-70°C  for  6  months. 


64 


6.4     Blood  Samples 

Blood  samples  may  be  required  for  biochemical  studies  of  haemoglobin  and  serum  or 
plasma  proteins,  blood  parasite  studies,  or  immunological  studies.  Although  blood 
samples  taken  in  the  field  may  be  stored  temporarily  on  wet  ice  and  brought  to  the 
laboratory  for  analysis,  generally  this  is  not  practical.  For  studies  of  blood  parasites, 
slides  can  be  prepared  directly  in  the  field.  Haemoglobin  or  serum  samples  obtained 
for  biochemical  analyses  should  be  quick-frozen  with  liquid  nitrogen  and  stored  in  a 
Styrofoam  cooler  with  dry  ice  as  described  in  section  6.3.  Once  samples  are  brought 
to  the  laboratory,  they  should  be  transferred  to  a  freezer  where  they  can  be  kept  for 
several  months. 

Mammals  should  be  anaesthetized  before  blood  is  taken.  Ether  is  an  effective 
anaesthetic  but  an  overdose  may  kill  the  animal.  Sudia  et  al.  (1970)  recommended 
carbon  dioxide  as  an  anaesthetic.  Mammals  can  be  bled  from  the  heart  using  a  2  or 
5  ml  disposable  syringe.  Clean  the  skin  of  the  area  to  be  punctured  with  cotton  soaked 
in  water  and  allow  to  dry.  If  you  require  plasma,  rinse  syringes  with  heparin  to 
prevent  coagulation.  For  such  mammals  as  mice,  use  a  25  gauge  %  inch  or  5/s  inch 
needle;  for  mammals  to  the  size  of  hares,  a  23  gauge  1  inch  needle;  and  for  mammals 
the  size  of  foxes  or  racoons,  an  18  gauge  1  V2  inch  needle.  For  small  rodents  and 
bats,  some  workers  prefer  to  take  blood  from  the  orbital  sinus.  Hold  the  mammal  in 
the  left  hand  with  the  thumb  exerting  sufficient  pressure  behind  the  eye  to  cause  the 
eye  to  bulge  out  slightly.  Insert  a  50  or  100  microlitre  micro-sampling  pipette 
(Corning  Glass  Company,  Corning,  New  York,  USA)  into  the  posterior  corner  of  the 
eye  and  gently  rotate  it  to  rupture  the  capillaries  against  the  bone.  Other  methods  that 
may  be  used  to  obtain  blood  include  venipuncture  and  skin  puncture  (Miale,  1972). 

Blood  from  syringes  or  micro-sampling  pipettes  should  be  discharged  into  vials 
(Sudia  et  al. ,  1970)  for  freezing  and  storage.  Label  each  vial  with  the  field  number  of 
the  specimen.  After  the  blood  sample  has  been  taken,  the  mammal  can  be  humanely 
killed  (see  section  5.1)  and  prepared  as  a  voucher  specimen. 

Slides  of  blood  smears  for  parasite  studies  are  easily  prepared  in  the  field. 
However,  there  are  several  precautions  to  follow  when  preparing  blood  slides.  Use 
new  slides  that  are  either  precleaned  by  the  manufacturer  or  cleaned  with  soap  and 
water  and  rinsed  in  95  per  cent  alcohol.  Wipe  with  a  lint  free  cloth  before  using.  If 
blood  is  obtained  by  cutting  a  vein,  pricking  tissue,  or  cutting  the  tail,  discard  the  first 
drop  from  the  syringe  to  get  rid  of  cellular  debris.  Use  the  second  drop  to  prepare  the 
blood  smear.  With  blood  obtained  directly  from  a  syringe  inserted  into  the  heart  or  a 
vein,  it  is  not  necessary  to  discard  this  first  drop.  Heparinized  blood  is  unsuitable  for 
blood  smears. 

Place  a  clean  microscope  slide  on  a  flat  surface  and  put  a  small  drop  of  fresh  blood 
about  3  cm  (1  inch)  from  the  end.  The  end  of  a  second  slide  (spreader  slide)  is  placed 
on  the  slide  in  front  of  the  drop  of  blood.  The  spreader  slide  should  be  maintained  at 
an  angle  of  about  30  degrees.  Pull  the  spreader  slide  back  onto  the  drop  of  blood. 
When  the  blood  has  spread  the  width  of  the  slide,  push  the  spreader  slide  forward 
with  a  fast,  steady  motion.  Keep  the  slide  flat  and  allow  the  smear  to  air  dry.  Once 
fixed  or  dried,  slides  can  be  stored  in  microscope  slide  boxes.  Label  each  slide  with 
the  field  number  of  the  specimen.  Follow  the  precautions  listed  in  section  6.1  for 
keeping  slides  free  of  dust.  Freshly  prepared  films  always  stain  best  but  if  the  slides 
cannot  be  stained  promptly,  fix  your  slides  in  absolute  ethanol  or  methanol.  For 


65 


detailed  information  on  preparing  blood  smears  and  blood  stains,  consult  Miale 
(1972)  and  Faust  et  al.  (1970). 

For  most  biochemical  studies  it  is  essential  to  separate  plasma  and  red  blood  cells 
and  best  results  will  be  obtained  by  centrifuging.  If  electricity  is  not  available,  several 
suitable  hand  centrifuges  are  available  (Fisher  Scientific  Company,  711  Forbes 
Avenue,  Pittsburgh,  Pennsylvania,  USA).  Transfer  the  fresh  whole  blood  samples  to 
centrifuge  tubes  and  centrifuge  at  3000  rev/min  for  20  min.  The  buff-coloured  layer 
(plasma)  can  be  separated  from  the  packed  cells  by  aspiration  with  a  micropipette. 
Transfer  the  plasma  to  glass  vials  or  tubes,  label,  and  freeze.  If  haemoglobin  is 
required,  red  blood  cells  should  be  haemolyzed.  Wash  the  cells  once  with  cold  0.85 
per  cent  saline  and  then  centrifuge  at  3000  rev/min  for  20  min.  Remove  the 
supernatant  by  aspiration  with  a  micropipette.  Add  two  volumes  of  distilled  water  to 
the  packed  cells.  After  mixing  thoroughly,  freeze  and  thaw  the  solution  three  times. 
Haemolysates  are  then  centrifuged  at  4000  rev/min  for  5  min.  Transfer  the 
supernatant  to  vials  and  quick-freeze  with  liquid  nitrogen. 


6.5     Preserving  Stomach  Contents 

Because  the  food  of  such  small  mammals  as  rodents  and  insectivores  is  usually 
ground  completely  by  the  teeth,  identification  of  food  items  requires  microscopic 
techniques.  These  usually  involve  preparation  of  microscope  slides  of  stomach 
contents  and  comparison  with  reference  slides  (Drodz,  1975;  Williams,  1962). 
Preparation  of  these  slides  can  be  tedious  and  time-consuming  and  the  collector  may 
wish  to  preserve  the  contents  of  stomachs  in  the  field  and  analyse  the  stomach 
material  at  his/her  convenience  in  the  laboratory. 

Dissect  stomachs  from  freshly  killed  specimens.  If  a  freezer  is  available,  the 
simplest  method  is  to  place  whole  stomachs  in  plastic  bags  or  vials  and  freeze  them. 
A  label  with  the  specimen's  field  number  should  be  placed  in  bags  or  vials.  Another 
method  is  to  remove  the  contents  of  stomachs  and  allow  the  material  to  dry.  Dried 
stomach  material  can  be  stored  in  paper  envelopes.  In  the  laboratory  the  desiccated 
material  from  stomachs  is  soaked  for  24  h  in  water  and  then  examined.  This 
technique,  however,  may  not  be  suitable  for  humid  climates.  A  third  method  is  to 
preserve  stomachs  and  their  contents  in  vials  with  80  per  cent  ethanol.  Make  an 
incision  through  the  stomach  wall  to  allow  the  solution  to  reach  stomach  contents. 
Record  the  field  number  on  a  sturdy  label  with  waterproof  ink  and  include  it  in  the 
vial. 


6.6     Preparation  of  Sperm  Slides 


For  Study  with  the  Light  Microscope 

Generally,  testes  from  freshly  killed  specimens  are  used  for  sperm  studies;  however, 
Hirth  (1960)  obtained  satisfactory  results  with  smears  of  the  Cauda  epididymis  of 
specimens  preserved  in  10  per  cent  formalin.  Spermatozoa  can  be  obtained  from  the 
cauda  epididymis  (Fig.  15)  or  the  seminiferous  tubules. 

66 


The  following  technique  was  used  by  Forman  (1968)  to  study  spermatozoa  in 
North  American  bats.  Place  the  whole  testis  in  a  fixing  solution  consisting  of  two 
parts  100  per  cent  methanol,  four  parts  95  per  cent  ethanol,  one  part  acetone,  two 
parts  chloroform  and  one  part  100  per  cent  propionic  acid.  To  permit  rapid  fixation, 
cut  the  testis  into  5  to  10  mm  squares.  Put  a  short  section  of  seminiferous  tubule  on  a 
slide  with  one  drop  of  lactophenol-cotton  blue  stain.  Lactophenol-cotton  blue  consists 
of  20  g  phenol  crystals,  0.05  g  cotton  blue  (Poirrier's  Blue,  National  Aniline 
Division),  20  ml  lactic  acid,  40  ml  glycerol,  and  20  ml  distilled  water.  Dissolve 
liquids  by  heating  under  hot  water  tap,  then  add  the  phenol  crystals  and  cotton  blue. 
Tease  the  tubule  apart  to  permit  spermatozoa  to  enter  the  staining  solution.  Place  a 
cover  slip  over  the  slide  and  seal  the  edges  with  balsam. 

Genoways  (1973)  used  the  following  method  for  comparing  spermatozoa  in 
various  species  of  spiny  pocket  mice  of  the  genus  Liomxs.  Remove  the  epididymis 
from  freshly  killed  specimens.  Take  a  small  amount  of  fluid  containing  sperm  and 
suspend  in  an  isotonic  solution  of  sodium  citrate  (prepared  fresh  each  day).  Place  a 
few  drops  of  the  suspension  on  a  microscope  slide  and  let  dry.  Then  fix  the 
spermatozoa  with  a  solution  of  one  part  glacial  acetic  acid  and  four  parts  absolute 
methanol  for  10  to  15  s.  Then  stain  the  sperm  slides  in  a  Coplan  jar  for  30  min  with  a 
0.02  solution  of  toluidine  blue  in  water. 

For  Study  with  the  Scanning  Electron  Microscope  (SEM) 

Several  recent  studies  have  shown  that  there  is  great  potential  for  studying  the 
morphology  of  mammalian  spermatozoa  with  the  SEM.  If  such  studies  are 
contemplated,  fix  the  testes  in  gluteraldehyde  in  the  field.  Remove  the  testes  from 
freshly  killed  specimens  and  wash  in  physiological  saline.  Place  the  testes  in  a  vial 
with  a  1  or  2  percent  solution  of  gluteraldehyde.  Gluteraldehyde  is  sold  commercially 
as  a  25  per  cent  solution  in  water  (J.  T.  Baker  Chemicals,  Canadian  Laboratory 
Supplies,  Toronto,  Canada).  The  testes  should  be  cut  into  5  to  10  mm  squares  to 
permit  rapid  fixation.  In  the  laboratory  tissue  is  washed  and  centrifuged  to  remove  the 
fixative  and  sperm  samples  are  freeze-dried  for  later  examination  with  the  SEM 
(Gould  et  al.,  1971). 


6.7     Fixing  Tissues  for  Histological  Study 

If  histological  studies  are  contemplated,  tissues  should  be  fixed  from  various  organs 
immediately  after  the  specimen  is  killed.  Proper  fixation  is  essential  for  preventing 
any  post-mortem  deterioration  in  tissues.  In  section  5  we  discussed  the  use  of 
buffered  neutral  formalin  for  fixing  entire  mammal  specimens.  Buffered  neutral 
formalin  is  also  an  excellent  general  purpose  fixative  for  histological  work  and  it  can 
be  used  to  fix  many  different  tissues.  For  certain  histological  procedures,  however, 
other  fixatives  may  be  desired  because  they  penetrate  tissues  more  rapidly  than 
neutralized  formalin  and  may  render  tissues  more  easily  stained  by  certain 
histological  dyes.  Tissues  can  be  left  in  some  fixatives  (e.g.,  buffered  neutralized 
formalin)  for  several  months;  with  other  fixatives  (e.g.,  Bouin's),  tissues  must  be 
transferred  to  alcohol  immediately  after  fixing.  Three  of  the  more  widely  used 


67 


fixatives  are  described  here.  For  more  information  on  fixatives  and  histological 
methods,  consult  Luna  (1968). 

Bouin's  Solution 

*picric  acid,  saturated  aqueous  solution  750  ml 

37-40%  formalin  250  ml 

glacial  acetic  acid  50  ml 

*if  not  stored  in  an  aqueous  solution,  picric  acid  is  highly  volatile. 

Bouin's  solution  is  frequently  used  for  fixing  gastrointestinal  tracts,  reproductive 
organs,  endocrine  glands,  and  brain  tissue.  It  is  a  rapid  fixative  and  will  fix  blocks  of 
tissues  in  4  to  12  h  depending  on  their  size.  Once  tissues  are  fixed,  however,  they 
must  be  washed  in  two  or  three  changes  of  40  per  cent  alcohol  for  4  to  6  h  to  remove 
all  picric  acid.  If  picric  acid  is  not  removed,  tissue  will  undergo  deleterious  changes. 
After  washing  tissues,  store  in  70  per  cent  alcohol. 

Alcohol-Formalin-Acetic  Acid  Solution  (AFA) 

37-40%  formalin  10  ml 

alcohol,  80%  90  ml 

glacial  acetic  acid  5  ml 

A  good  fixative  for  rapid  fixation,  AFA  solution  has  been  used  for  reproductive 
and  gastrointestinal  tracts.  Small  pieces  of  tissue  (2  mm  thick)  will  completely  fix  in 
4  to  6  h.  AFA  is  not  suitable  for  tissue  storage  and  the  fixed  tissue  should  be 
transferred  to  70  per  cent  alcohol. 

Formalin-Sodium  Acetate  Solution 

37^0%  formalin  100  ml 

sodium  acetate  20  g 

tap  water  900  ml 

This  is  an  excellent  fixative  in  which  to  store  gross  blocks  of  tissue  (e.g.,  whole 
brains  of  such  small  mammals  as  bats,  shrews,  or  mice). 


7.     Shipping  Specimens 


7.1     Methods  for  Shipping 


Fluid-preserved  Specimens 

Once  properly  fixed,  specimens  can  be  shipped  "damp  packed",  that  is,  only  a  small 
amount  of  10  per  cent  formalin  is  added  to  the  packing  material  in  the  container  to 
keep  specimens  moist  in  transit.  About  0.25  L  (0.5  pt)  of  fluid  is  sufficient  for  a 

68 


container  of  3.8  L  (1  gal.).  Cotton  wool  or  newspaper  should  be  added  to  each 
package,  both  to  limit  the  movement  of  specimens  and  to  retain  the  dampness. 
Wide-mouthed  plastic  jars  are  the  most  suitable  shipping  containers  but  if  they  are  not 
available,  plastic  bags  may  be  used  if  they  are  well  sealed.  Glass  jars  are  the  least 
desirable  type  of  container  but  can  be  used  if  properly  packed  in  a  strong  container 
and  insulated  with  at  least  5  cm  (2  inches)  of  wadded  paper  or  similar  material  on  all 
sides  of  each  jar.  If  plastic  bags  are  used,  it  is  recommended  that  the  specimens, 
cotton  wool,  and  fluid  be  placed  in  one  bag  and  sealed  by  tying  the  top  of  the  bag;  be 
certain  to  remove  excess  air  from  the  bag.  Then  place  the  sealed  bag  inside  a  second 
bag,  which  is  in  turn  sealed  by  careful  tying.  The  double  plastic  bag  should  then  be 
placed  in  a  light,  strong  container.  A  tin  can  with  a  lid  is  ideal.  If  the  tin  is  too  large, 
fill  the  remaining  space  with  cotton  wool  or  crushed  paper.  The  container  should  be 
large  enough  to  absorb  the  fluid  should  the  bags  leak.  Seal  tin  cans  with  adhesive  tape 
to  ensure  they  will  not  open  or  leak  in  transit.  Generally,  packages  should  be  kept 
small  enough  so  that  they  may  be  shipped  by  ordinary  parcel  post. 

Skins  and  Skulls 

It  is  advisable  to  ship  study  skins  in  small,  strong  containers,  preferably  plywood 
boxes,  although  strong  cardboard  boxes  may  be  used.  Begin  packing  by  placing  a 
layer  of  about  5  cm  (2  inches)  of  cotton  wool  or  similar  material  on  the  bottom, 
followed  by  a  layer  of  dried  skins.  Add  another  layer  of  cotton  wool  and  repeat  the 
process  with  another  layer  of  skins,  until  the  box  is  almost  full.  Allow  a  top  layer  of 
about  5  cm  (2  inches)  of  cotton  wool. 

If  thoroughly  dried  and  free  of  insects  and  insect  eggs,  skulls  may  be  packed  in  the 
same  box  with  skins.  Otherwise,  ship  them  in  a  separate  strong  container  that  cannot 
be  smashed  or  crushed  under  normal  shipping  conditions.  If  the  skins  are  likely  to  be 
in  transit  for  longer  than  a  few  days,  add  moth  balls  (paradichlorobenzine)  to  the 
container  of  skins,  to  protect  them  from  moths  or  dermestid  beetle  eggs.  Skulls  and 
skeletons  should  not  be  placed  together  in  a  container  with  moth  balls  because  the 
chemical  released  may  inhibit  the  activity  of  dermestid  beetles  that  are  used  by  most 
museums  to  clean  skulls  and  skeletons. 

Skeletons 

Skeletons  must  be  dried  before  shipping.  You  can  pack  small  skeletons  in  the  same 
container  used  for  the  skins  if  moth  crystals  have  not  been  added  to  the  container. 
Place  the  skeletons  on  the  bottom  of  the  container,  then  cover  with  alternate  layers  of 
cotton  and  skins.  Heavy  bones  from  large  mammals  should  be  packed  separately  in 
sturdy  wooden  crates.  If  a  large  skeleton  is  properly  dried,  place  it  in  a  plastic  bag  just 
before  shipping  to  reduce  the  odour.  Collectors  shipping  large  skeletons  should  notify 
the  receiving  museum  prior  to  shipping. 

Data 

Pages  of  the  original  field  catalogue,  field  notes,  and  any  pertinent  topographic  maps 
should  be  mailed  separately  from  specimens  as  first  class  or  air  mail  and  registered  if 
from  a  country  where  mail  service  is  inadequate. 

69 


7.2     Import/Export  Regulations 


Convention  on  International  Trade  in  Endangered  Species 

Canada,  the  United  States,  and  approximately  40  other  countries  have  signed  a 
Convention  on  International  Trade  in  Endangered  Species.  The  Convention  prohibits 
all  imports  and  exports  of  protected  species  except  under  permit.  These  regulations 
apply  to  all  international  shipments  and,  in  addition  to  living  mammals,  to  parts  and 
derivatives  of  endangered  species.  Permit  requirements  must  be  observed  for  any 
shipment  to  or  from  a  member  country,  even  if  the  other  country  involved  is  not  a 
member  of  the  Convention.  Species  protected  are  listed  in  three  Convention 
appendices.  Appendix  I  of  the  Convention  lists  species  threatened  with  extinction; 
Appendix  II  lists  species  that  must  be  monitored  to  avoid  the  threat  of  extinction;  and 
Appendix  III  lists  species  placed  there  by  individual  countries  to  reinforce  domestic 
conservation  measures.  All  shipments  of  species  listed  in  Appendix  I  of  the 
Convention  require  two  permits — one  from  the  importing  country  and  another  from 
the  exporting  country.  Export  permits  must  be  issued  from  the  country  of  origin  for 
species  listed  in  Appendix  II.  International  shipments  of  Appendix  III  species  require 
either  an  export  certificate  from  the  country  that  listed  the  species  or  a  certificate  of 
origin  from  any  country. 

Shipments  to  Canada 

All  shipments  to  Canadian  museums  should  be  labelled  with  a  declaration  form  that 
indicates  the  total  number  of  specimens,  the  general  kind  of  specimens  (bats  or 
rodents),  and  that  specimens  are  preserved  (e.g.,  100  preserved  bats)  rather  than  live 
or  frozen.  Shipments  of  living  mammals  must  have  Canadian  Department  of 
Agriculture,  Health  of  Animal  Branch  permits. 

The  shipment  should  also  be  marked  "No  Commercial  Value  (NCV),  For 
Scientific  Research,  No  Endangered  Species".  If  the  collector  insures  the  shipment 
for  more  than  $150.00,  he  must  complete  special  Canada  Customs  invoice  forms  for 
shipments  from  outside  Canada;  these  invoice  forms  are  available  from  museums 
upon  request.  Shipments  should  also  be  labelled  "In  Bond  to  Destination"  which 
ensures  that  the  shipment  can  only  be  inspected  by  customs  officials  at  the  destination 
and  not  at  border  points.  Notify  the  museum  of  a  forthcoming  shipment  and,  when 
sending  specimens  by  air  freight,  forward  a  copy  of  the  Airway  Bill. 

Permits  to  import  or  export  species  listed  under  the  Convention  on  International 
Trade  in  Endangered  Species  may  be  obtained  from  the  Canadian  Wildlife  Service  in 
Ottawa  or  any  provincial  or  territorial  wildlife  headquarters. 

Shipments  to  the  United  States 

Packages  should  be  clearly  marked  on  the  outside  with  the  name  and  address  of  the 
shipper  and  of  the  consignee  and  give  an  accurate  statement  of  the  contents  (species 
and  numbers  of  each  species).  Label  the  package  "Scientific  Specimens;  No 
Endangered  Species;  No  Commercial  Value". 


70 


DESIGNATED  PORTS  OF  ENTRY 

Nonendangered  mammals  and  parts  thereof  from  countries  other  than  Canada  may 
enter  or  leave  the  US  without  a  permit  only  through  eight  designated  ports  of  entry: 
Los  Angeles,  San  Francisco,  Miami,  Honolulu,  Chicago,  New  Orleans,  New  York, 
and  Seattle.  Species  protected  under  the  Convention  on  International  Trade  in 
Endangered  Species  and  the  US  Endangered  Species  Act  must  enter  the  US  through 
these  same  eight  cities.  Mammals  other  than  endangered  species  may  be  imported, 
for  final  destination  only,  into  Alaska  through  Anchorage,  Fairbanks,  Juneau,  or  Tok 
Junction;  or  into  either  Puerto  Rico  or  the  Virgin  Islands  through  San  Juan,  Puerto 
Rico. 

Specimens  obtained  legally  in  Canada  may  enter  the  USA  without  permit  through 
any  of  25  border  points  if  no  endangered  species  are  included.  Contact  the  Division  of 
Law  Enforcement,  US  Fish  &  Wildlife  Service,  Washington,  D.C.,  USA  for  a  list  of 
these  border  points.  If  no  endangered  species  are  included,  mammals  collected 
legally  in  Mexico  may  enter  the  US  without  permit  through  any  of  seven  border 
points:  Calexico  or  San  Diego-San  Ysidro,  California;  Nogales  or  San  Luis,  Arizona; 
Brownsville,  El  Paso,  or  Laredo,  Texas. 

Scientific  specimens  of  nonendangered  species  may  enter  or  leave  the  US  at 
nondesignated  ports  of  entry  under  permit. 

PERMITS 

To  import  specimens  through  the  designated  ports  of  entry  previously  given,  the 
collector  needs  a  valid  collecting  permit  and  an  export  permit  (if  required  by  the 
country  of  origin)  and  a  Declaration  of  Importation  of  Fish  &  Wildlife  (Form  3-177). 
You  must  file  copies  of  these  documents  with  the  District  Director  of  Customs  at  the 
port  of  entry. 

For  importation  of  mammal  specimens  through  nondesignated  ports  of  entry,  you 
must  satisfy  the  previously  given  requirements  and  have  a  permit  for  the 
nondesignated  port  from  the  U.S.  Fish  &  Wildlife  Service. 

Permits  for  importing  specimens  of  mammals  listed  in  the  Convention  on 
International  Trade  in  Endangered  Species  of  the  federal  Endangered  Species  Act  can 
be  obtained  from  the  Federal  Wildlife  Permit  Office,  U.S.  Fish  &  Wildlife  Service, 
Washington,  DC  20240,  USA.  Note  that  although  some  species  of  mammals  are 
listed  in  both  the  convention  and  the  Endangered  Species  Act,  the  two  lists  do  not 
contain  identical  species. 

A  permit  is  required  to  import  living  material,  including  tissue  cultures,  cell  lines, 
and  blood  and  serum  that  could  serve  as  a  vector  for  pathogenic  organisms.  Apply  to 
the  U.S.  Department  of  Agriculture,  Animal  and  Plant  Health  Inspection  Service, 
Veterinary  Services,  Washington,  D.C.,  USA  for  this  permit. 

INTERSTATE  TRANSPORT  OF  MAMMAL  SPECIMENS 

Packages  or  containers  in  which  specimens  are  transported  must  be  clearly  marked  on 
the  outside  with  the  same  information  as  described  for  shipments  from  outside  the 
US.  Because  it  is  illegal  under  the  Lacey  Act  to  import  or  ship  in  interstate  commerce 
any  wildlife  taken  in  violation  of  state  or  local  laws,  scientific  collectors  must 
familiarize  themselves  with  appropriate  laws  for  the  state  or  region  concerned. 


71 


8.     Public  Health  Hazards 


It  is  beyond  the  scope  of  this  manual  to  discuss  the  numerous  potentially  dangerous 
diseases  that  are  carried  by  wild  mammals.  Several  useful  references  are  given  in  the 
bibliography.  Because  diseases  are  often  local  in  their  distribution,  it  is  impossible  to 
list  specific  diseases  that  the  collector  may  encounter.  As  a  result,  you  are  advised  to 
familiarize  yourself  with  the  disease  hazards  that  may  be  present  in  your  local  area. 
Consult  your  physician  about  vaccinations  that  may  be  taken  against  diseases  in  your 
area,  for  example,  rabies,  plague.  All  collectors  should  be  vaccinated  against  tetanus. 
Take  care  to  avoid  being  bitten  when  handling  live  mammals  and  use  leather  gloves 
to  protect  the  hands.  If  you  are  collecting  species  that  are  susceptible  to  rabies  (bats, 
foxes,  mongooses,  skunks),  regard  all  captures  as  potentially  rabid.  Some  common 
sense  precautions  to  reduce  health  hazards  can  be  followed  when  preparing 
specimens.  Wear  rubber  gloves  when  dissecting  mammals  and,  for  additional 
protection,  use  disposable  paper  face  masks.  Avoid  contact  with  urine  and  faeces, 
which  often  contain  infectious  agents.  Dissecting  instruments  should  be  cleaned  and 
disinfected  with  Dettol  or  a  3  per  cent  phenol  solution  after  use.  Immediately  wash 
any  cuts  or  abrasions  with  soap  and  treat  with  an  antiseptic.  Use  similar  precautions 
when  handling  road  kills.  If  symptoms  such  as  chronic  respiratory  distress, 
influenza-like  sickness,  swelling  of  lymph  nodes,  high  temperature,  vomiting,  or 
diarrhoea  occur  in  conjunction  with  the  handling  of  specimens,  they  should  be 
regarded  with  suspicion  and  medical  advice  should  be  sought. 


9.     Acknowledgements 


We  gratefully  acknowledge  the  assistance  and  encouragement  of  staff  of  the 
Department  of  Mammalogy,  ROM,  during  the  preparation  of  the  manuscript.  The 
following  staff  deserve  special  thanks:  J.  R.  Tamsitt  for  his  advice  on  special 
techniques  and  for  critically  reviewing  the  manuscript,  Judith  Eger  for  critically 
reviewing  the  manuscript,  Sophie  Poray  for  drawing  some  of  the  illustrations,  and 
Nancy  Grepe  for  typing  the  numerous  revisions  of  the  manuscript.  Other  illustrations 
were  done  by  Anker  Odum  and  Julian  Mulock,  Exhibit  Design  Services,  ROM.  The 
cover  drawing  is  by  Peter  Buerschaper,  Exhibit  Design  Services,  ROM.  Many  of  the 
techniques  described  in  the  manual  for  preparing  study  skins  were  developed  by  John 
G.  Williams. 


72 


10.     Selected  Bibliography 


General  Reference 

ANDERSON.  R    M 

1965  Methods  of  collecting  and  preserving  vertebrate  animals.  4th  ed.  rev.     National  Museum  of 
Canada,  Bulletin  69:1-199. 

BRITISH  MUSEUM  (NATURAL  HISTORY) 

1968       Instructions  for  collectors  no.  1.  Mammals  (non-marine).  2nd  ed.     British  Museum  (Natural 
History)  Publication  665:1-55. 

brown,  j  c  and  d  m  stoddart 

1977       Killing  mammals  and  general  post-mortem  methods.     Mammal  Review  7:63-94. 

deblase.  a  f  and  r  e  martin 

1974       A  manual  of  mammalogy  with  keys  to  the  families  of  the  world.     Dubuque,  W.  C.  Brown. 
329  pp. 

Giles.  R.H..  Jr.,  ed. 

1971       Wildlife  management  techniques.  3rd  ed.  rev.  Washington,  DC,  The  Wildlife  Society.  633 
pp. 

HALL,  e  r 

1962       Collecting  and  preparing  study  specimens  of  vertebrates.     University  of  Kansas,  Museum  of 
Natural  History,  Miscellaneous  Publication  30:1-46. 

KNUDSEN.  J    W 

1966  Biological  techniques;  collecting,  preserving,  and  illustrating  plants  and  animals.  New  York, 
Harper  &  Row.  525  pp. 

PETERSON.  R    L 

1965       Collecting  bat  specimens  for  scientific  purposes.     Toronto,  Dept.  of  Mammalogy,  Royal 
Ontario  Museum.  8  pp. 

WILLIAMS.  S.L.,  R.  LAUBACK.  and  H    H    GENOWAYS 

1977       A  guide  to  the  management  of  recent  mammal  collections.     Camegie  Museum  of  Natural 
History,  Special  Publication  4:1-106. 

Equipment 

DOWLER.  R   C    and  H    H   GENOWAYS 

1976       Supplies  and   suppliers  for  vertebrate  collections.     Museology,   Texas  Tech   University, 
4:1-83. 


Locality  Data 

AXTELL,  R    W 

1965       More  on  locality  data  and  its  presentation.     Systematic  Zoology  14:64—66. 

REIMER.  w   j 

1954       Formulation  of  locality  data.     Systematic  Zoology  3: 138-140. 

Mammal  Collecting 

BAKER.  R   J    and  S    L   WILLIAMS 

1972       A  live  trap  for  pocket  gophers.     Journal  of  Wildlife  Management  36:1320-1322. 


73 


GREENHALL.  A    M    and  1   L   PARADISO 

1968       Bats  and  bat  banding.     United  States  Dept.  of  the  Interior,  Bureau  of  Sport  Fisheries  and 
Wildlife,  Resource  Publication  72:1^47. 

MANITOBA  DEPT   OF  RENEWABLE  RESOURCES  AND  TRANSPORTATION  SERVICE 

1965       The  Manitoba  trappers'  guide.  Rev.  ed.   Winnipeg,  Dept.  of  Renewable  Resources  and 
Transportation  Service.  122  pp.  [good  review  of  trapping  and  skinning  methods] 

NELLES.  C.  H    and  R    D    TABER 

1974       A  conical  pitfall  trap  for  small  mammals.     Northwest  Science  48:102-103. 

STAINS,  H    j 

1962       Game  biology  and  game  management:  a  laboratory  manual.     Minneapolis,  Burgess.  143  pp. 
[trapping  methods] 

TIDEMAN.  C    R    and  D   P    WOODSIDE 

1978       A   collapsible   bat-trap   and   a  comparison   of  results   obtained   with   trap   and   with   mist 
nets.     Austrialian  Wildlife  Research  5:355-362. 

TUTTLE,  M    D 

1974  An  improved  trap  for  bats.     Journal  of  Mammalogy  55:475-477. 

1976  Collecting  techniques.  In  Baker,  R.J.  et  al.,  eds..  Biology  of  bats  of  the  New  World  family 
Phyllostomatidae  Part  I.  Texas  Tech  University,  Musuem,  Special  Publications  10:71-88. 

twigg,  G  I 

1975  Catching  mammals.     Mammal  Review  5:83-100. 

WEINER.  J   G    and  H    G    SMITH 

1972       Relative  efficiencies  of  four  small  mammal  traps.     Journal  of  Mammalogy  53:868-873. 

WINGATE.  L   R    and  J    MEESTER 

1977  A  field  test  of  six  types  of  live-trap  for  african  rodents.     Zoologica  Africana  12:215-223. 

YATES,  T   L    and  D   J    SCHMIDLY 

1975       Karyotype  of  the  eastern  mole  (Scalopus  aquaticus),  with  comments  on  the  karyology  of  the 
family  Talpidae.     Journal  of  Mammalogy  56:902-905.  [description  of  a  live  trap  for  moles] 

Preparation 

DOWNING.  S.  C 

1945       Color  changes  in  mammal  skins  during  preparation.     Journal  of  Mammalogy  26:128-132. 

QUAY,  w    M 

1974       Bird  and  mammal  specimens  in  fluid — objectives  and  methods.     Curator  17:91-104. 

setzer.  H  w 

1968       Directions  for  preserving  mammals  for  museum  study.     United  States  National  Museum, 
Smithsonian  Institution,  Information  Leaflet  380:1-19. 

smith.  D  A 

1968       On  the  use  of  tapered  wires  for  study  skins  of  small  mammals.     Journal  of  Mammalogy 
49:787-790. 

Public  Health 

IRVIN.  A   d    and  J    E   COOPER 

1972       Possible  health  hazards  associated  with  the  collection  and  handling  of  post-mortem  zoological 
material.     Mammal  Review  2:43-54. 


74 


McDIARMID,  A  ,  ed. 

1969  Diseases  in  free-living  wild  animals.  Zoological  Society  of  London,  Symposium  24. 
London,  Academic  Press.  332  pp. 

Regulations 

ASSOCIATION  OF  SYSTEMATICS  COLLECTIONS 

1977  Index  (o  U.S.  federal  wildlife  regulations.  Lawrence,  University  of  Kansas,  Museum  of 
Natural  History.  278  pp. 

CANADIAN  WILDLIFE  SERVICE 

1973  Convention  on  international  trade  in  endangered  species  of  wild  flora  and  fauna.  Canadian 
Wildlife  Service  reprint.  Ottawa,  Environment  Canada.  20  pp. 

EDWARDS.  S    R    and  L    D   GROTTA.  eds. 

1976  Systematics  collections  and  the  law.  Lawrence,  Association  of  Systematics  Collections.  29 
pp. 

GENOWAYS.  H    H    and  J    R   CHOATE 

1976  Federal  regulations  pertaining  to  collection,  import,  export  and  transport  of  scientific 
specimens  of  mammals.     Journal  of  Mammalogy  57(2)  suppl.:  1-9. 

McGAUGH,  M    H    and  H    H    GENOWAYS 

1976  State  laws  as  they  pertain  to  scientific  collecting  permits.  Museology,  Texas  Tech 
University,  2:1-81. 

SINGLETON.  M. 

1977  Endangered  species  legislation  in  Canada.  In  Mosqin,  T.  and  C.  Suchal,  eds.,  Canada's 
threatened  species  and  habitats.     Canadian  Nature  Federation,  Special  Publication  6: 19-21. 

Reproductive  Data 

CONWAY.  C   H 

1955  Embryo  resorption  and  placental  scar  formation  in  the  rat.  Journal  of  Mammalogy 
36:516-532. 

ECKSTEIN,  P    and  S   ZUCKERMAN 

1956  Morphology  of  the  reproductive  tract.  In  Parkes,  A.  S.,  ed.,  Marshall's  physiology  of 
reproduction,  vol.  1,  pt.  1.     London,  Longman  Green,  pp.  43-155. 

JAMESON,  E    W  .  Jr. 

1950       Determining  fecundity  in  male  small  mammals.     Journal  of  Mammalogy  31:433^*36. 

ROLAN.  R    G    and  H    T    GIER 

1967  Correlation  of  embryo  and  placental  scar  counts  of  Peromxscus  manic  ulaius  and  Microtus 
ochrogasier .     Journal  of  Mammalogy  48:317-319. 

Special  Techniques 

BAKER.  R    J 

1970  The  role  of  karyotypes  in  phylogenetic  studies  of  bats.  In  Slaughter,  B.  H.  and  D.  W.  Walton, 
eds..  About  bats:  a  chiropteran  biology  symposium.  Dallas,  Southern  Methodist  University 
Press,  pp.  303-312. 

DRODZ.  A 

1975  Analysis  of  stomach  contents  of  small  mammals.  //;  Grodzinski,  W.,  R.  Z.  Klekowski,  and  A. 
Duncan,  eds.,  Methods  for  ecological  bioenergetics.  IBP  handbook  24.  Oxford,  Blackwell 
Scientific,  pp.  337-341. 

75 


FAUST.  E.  C,  P   F.  RUSSELL,  and  A   C   JUNG 

1970  Craig  and  Faust's  clinical  parasitology.  8th  ed.     Philadelphia,  Lea  and  Febiger.  890  pp. 

FORMAN,  G    L 

1968  Comparative  gross  morphology  of  spermatozoa  of  two  families  of  North  American 
bats.     University  of  Kansas  Science  Bulletin  16:901-928. 

GENOWAYS.  H    H 

1973  Systematics  and  evolutionary  relationships  of  spiny  pocket  mice,  genus  Liomvs.  Texas  Tech 
University,  Museum,  Special  Publications  5:1-292.  [technique  for  preparing  rodent  sperm 
slides] 

GOULD.  K.  G.,  L.  J    D   ZANEVELD,  and  W    L   WILLIAMS 

1971  Mammalian  gametes:  a  study  with  the  scanning  electron  microscope.  Chicago,  Proceedings 
of  the  Fourth  Annual  Scanning  Electron  Microscope  Symposium,  part  1,  pp.  289-295. 

hirth.  M  F 

1960  The  spermatozoa  of  some  North  American  bats  and  rodents.  Journal  of  Morphology 
106:77-83. 

KAISER.  M    N    and  H    HOOGSTRAAL 

1968  Simple  field  techniques  and  laboratory  method  for  recovering  living  ticks  (Ixoidea)  from 
hosts .     Journal  of  Parasitology  54 : 1 88- 1 89 . 

LUNA.  L.  G 

1968         Manual  of  histological  staining  methods  of  the  Armed  Forces  Institute  of  Pathology.  3rd 
ed.     New  York,  McGraw  Hill.  258  pp. 

MEYER,  M   C    and  O   W    OLSEN 

1971  Essentials  of  parasitology.     Dubuque,  W.  C.  Brown.  305  pp. 

MIALE,  J.  B. 

1972  Laboratory  medicine:  hematology.  4th  ed.     Saint  Louis,  C.  V.  Mosby.  1318  pp. 

SELLER,  M    J. 

1971  Direct  and  repeatable  bone  marrow  chromosome  preparations  from  living  mice.  Stain 
Technology  46:285-288. 

SUDIA.  W    D  ,  R    D   LORD,  and  R   O    HAYES 

1970  Collection  and  processing  of  vertebrate  specimens  for  arbovirus  studies.  Washington, 
United  States  Dept.  of  Health,  Education,  and  Welfare,  Public  Health  Service.  65  pp. 

watson.  g  e  and  a  b  amerson.  Jr. 

1967  Instructions  for  collecting  bird  parasites.  United  States  National  Museum,  Smithsonian 
Institution,  Information  Leaflet  477:1-12. 

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76 


1 1 .     Appendices 


11.1     Appendix  1 

Checklist  of  Field  Equipment 

For  a  listing  of  suppliers  of  field  equipment,  consult  Dowler  and  Genoways  (1976). 

Collecting  Bats 

mist  nets— 12.5  m  x  2  m  (42  ft  x  7  ft),  9  m  x  2  m  (30  ft  x  7  ft) 

hand  net 

machete — for  cutting  poles 

headlamp  and  batteries — for  working  in  caves  or  checking  nets  at  night 

flashlight 

long  forceps  (25  cm;  10  inches) — for  collecting  bats  in  attics  or  rock  crevices 

cloth  collecting  bags 

leather  gloves — for  handling  live  specimens 

Collecting  Other  Mammals 

museum  special  snap  traps 

Victor  rat-traps 

Sherman  live  traps 

juice  or  coffee  cans — for  pitfall  traps 

cloth  collecting  bags 

bait — peanut  butter,  rolled  oats,  dried  fruits,  nuts 

coloured,  plastic  flagging  tape — for  marking  trap  sites 

compass  and  topographic  maps  of  study  areas 

tobacco  tin  or  plastic  jar — for  carrying  bait 

knapsack — for  carrying  traps 

cord,  wire — for  tying  traps  to  stakes 

guns,  ammunition 

leather  gloves 

cotton  wool — nesting  material  for  live  traps 

Measuring  and  Preparing  Specimens 

weight  scales  (metric) — Pesola  spring  balances 

metal  tape-measure  (metric),  plastic  ruler  (metric) 

catalogue  sheets 

field  tags,  waterproof  paper 

hand  lens — for  examining  external  genitalia  and  internal  sex  organs 

notebook — for  field  notes 

pencils,  pen,  and  waterproof  ink 


77 


small  waterproof  tags — for  labelling  vials 
small  vials  (\-4  dram  size) — for  embryos  and  parasites 
borax  or  magnesium  carbonate  powder 
gauze  or  cheesecloth  bags — for  skulls  and  skeletons 
disinfectant  (Dettol  or  3%  phenol) — for  sterilizing  dissecting  instruments 
sawdust  or  cornmeal 
toothbrush— for  brushing  fur 
disposable  gloves 

chloroform  or  ether — for  killing  small  mammals 
Euthanyl  (sodium  pentobarbital) — for  killing  larger  mammals 
70  per  cent  ethanol — for  ectoparasites,  cleaning  blood  off  fur 
40  per  cent  formaldehyde,  salts  for  neutralizing  formalin 
hypodermic  syringe  and  needles — for  injecting  specimens 
plastic  bags,  various  sizes 
moth  balls  (paradichlorobenzene  crystals) 
cotton — for  stuffing  study  skins 

wire  for  tails  of  skins — no.  12,  16,  18,  20,  22,  24,  25  gauge  (preferably  Monel  wire) 
glass-headed  pins,  various  sizes 
needles,  various  shapes  and  sizes 
pinning  board,  corkboard,  or  wallboard 
assortment  of  cardboard  or  art  board — for  flat  skins 
white  linen  thread,  sizes  40,  30,  25 
white  cotton  thread,  sizes  50,  60 
pliers,  wire  cutters 

drying  chest — for  storing  drying  skins 
scalpel  handle,  no.  3  and  no.  4  sizes 

scalpel  blades,  no.  20  size  (for  no.  4  handle)  and  no.  10  size  (for  no.  3  handle) 
scissors,  one  small  pair  with  sharp  points,  one  large  pair 
forceps,  one  pair  with  fine  tips,  one  pair  with  blunt  tips 
bone  cutters 

skinning  knife — for  large  mammals 
sharpening  stone 

table  salt  (NaCl) — for  drying  large  skins 
burlap  sacks — for  skulls  and  bones  of  large  mammals 
masking  tape 

electrical  or  adhesive  tape — for  securing  lids  on  glass  vials  and  taping  lids  of  mailing 
containers 


11.2     Appendix  2 


Karyotype  Kit  for  120  Small  Mammals 

Sodium  citrate  15  packages  of  0.5  g  quantity 

5  packages  of  0.75  g  quantity 
1  hand  centrifuge 
24-15  ml  glass  centrifuge  tubes 
24-1  ml  tuberculin  syringes 


78 


2-2  ml  Luer  Lock  syringes 

4-5  ml  Luer  Lock  syringes 

1  doz.  no.  26  syringe  needles  (Vi  inch) 

1  doz.  no.  24  syringe  needles  (1  inch) 

1  doz.  no.  21  syringe  needles  (1  l/z  inches) 

250  (1  box)  disposable  glass  pipettes  (5.75  inches) 

48  rubber  pipette  bulbs 

1  plastic  centrifuge  rack 

2  centrifuge  tube  cleaning  brushes 

5  gross  (720)  precleaned  microscope  slides  with  frosted  ends  (75  mm  x  25  mm  size) 

3  pints  absolute  methanol 
2  pints  glacial  acetic  acid 
4-10  mg  vials  Velbe 

2-100  ml  serum  bottles  of  bacteriostatic  sodium  chloride 

1-125  ml  nalgene  Erlenmeyer  flask — for  sodium  citrate  solution 

9  slide  boxes  (100  slide  capacity) 

1-100  ml  nagrene  Erlenmeyer  flask — -for  fixative 

1-50  ml  nagrene  graduated  cylinder  for  measuring  fixative 

matches 

silica  gel  crystals 

grease  pencil — for  labelling  centrifuge  tubes 

100  ml  distilled  water 

For  Staining 

500  ml  xylol 

500  ml  acetone 

100  ml  Giemsa  stain 

100  ml  permount 

5-1  oz.  boxes  cover  slips  (no.  1,  24  mm  x  50  mm) 

6  Coplan  jars 

1-50  ml  polypropylene  graduated  cylinder — for  measuring  stain 
1  polypropylene  funnel,  filter  paper — for  filtering  stain 


79 


ISBN  0-88854-255-0 
ISSN  0082-5093