OCCASIONAL PAPERS
o he
MUSEUM OF NATURAL HISTORY
The Uni e si y o Kansas
Law ence, Kansas
NUMBER 54, PAGES 1-38 MAY 12, 1976
POPULATION ECOLOGY OF THE GRAY BAT
(MYOTIS GRISESCENS): PHILOPATRY, TIMING
AND PATTERNS OF MOVEMENT, WEIGHT LOSS
DURING MIGRATION, AND SEASONAL
ADAPTIVE STRATEGIES
By
MERLIN D. TuTILE1
ABSTRACT
An in ensi e banding and eco e y s udy o M. g isescens esul ed in 19,691
eco e ies a 120 loca ions. Included we e many mul iple ecap u es and
ound ip eco e ies be ween ma e ni y and hibe na ing ca es. G ay ba s
demons a ed s ong loyal y o a summe home ange, o en including six o
mo e ca es, as well as o hei win e ing si e. Adul emales eme ged om
hibe a ion i s , in ea ly Ap il, ollowed by yea lings o bo h sexes and las ly by
adul males. Once a he summe home ange, adul emales cong ega ed in
one p e e ed ma e ni y si e o ea young, while adul males and yea lings
clus e ed in smalle g oups, usually in ca es o he han he ma e ni y ca e.
A e l1e ledging o young, sex and age seg ega ion weakened, and indi
iduals we e mo e e enly dispe sed h nugh he home ange. Fall mig a ion
ook place in app oxima ely l1e same o de as sp ing eme gence, wi h adul
emales lea ing in ea ly Sep embe and ju eniles emaining behind wi h ile
las males o lea e, usually by mid-Oc obe . Dis ances egula ly a eled in ·
mig a ion anged om 17 o 437 km ( one way, di ec dis ance), wiili nea ly
he en i e sou heas e n popula ion cong ega ing in h ee majo hibe nacula.
Mig a o y mo emen s appea ed o be di ec and apid o adul emales in
pa icula , and weigh loss du ing mig a ion was di ec ly p opo ional o
dis ance a eled. No signi ican win e mo emen s we e obse ed a e
hibe na ion began.
INTRODUCTION
Much is known abou he leng h and app oxima e iming o
mig a o y mo emen s o ba s. Mye s ( 1964) and Hall and Wilson
• Ve eb a e Di ision, Milwaukee Public Museum, Mllwauke�, Wisconsln 153233.
,../
-
