ORIGINAL PAPER
Bat colony size reduction coincides with clear-fell harvest
operations and high rates of roost loss in plantation forest
Kerry M. Borkin
•
Colin O’Donnell
•
Stuart Parsons
Received: 30 March 2011 / Accepted: 11 August 2011 / Published online: 3 September 2011
Ó Springer Science+Business Media B.V. 2011
Abstract Clear-fell harvest of forest concerns many wildlife biologists because of loss of
vital resources such as roosts or nests, and effects on population viability. However, actual
impact has not been quantified. Using New Zealand long-tailed bats (Chalinolobus
tuberculatus) as a model species we investigated impacts of clear-fell logging on bats in
plantation forest. C. tuberculatus roost within the oldest stands in plantation forest so it was
likely roost availability would decrease as harvest operations occurred. We predicted that
post-harvest: (1) roosting range sizes would be smaller, (2) fewer roosts would be used, and
(3) colony size would be smaller. We captured and radiotracked C. tuberculatus to day-
roosts in Kinleith Forest, an exotic plantation forest, over three southern hemisphere
summers (Season 1 October 2006–March 2007; Season 2 November 2007–March 2008;
and Season 3 November 2008–March 2009). Individual roosting ranges (100% MCPs) post
harvest were smaller than those in areas that had not been harvested, and declined in area
during the 3 years. Following harvest, bats used fewer roosts than those in areas that had
not been harvested. Over 3 years 20.7% of known roosts were lost: 14.5% due to forestry
operations and 6.2% due to natural tree fall. Median colony size was 4.0 bats
(IQR = 2.0–8.0) and declined during the study, probably because of locally high levels of
roost loss. Post harvest colonies were smaller than colonies in areas that had not been
harvested. Together, these results suggest the impact of clear-fell harvest on long-tailed bat
populations is negative.
Keywords Chalinolobus tuberculatus Á Clear-fell harvest Á Colony Á Logging Á
Production forest Á Roost loss
K. M. Borkin Á S. Parsons (&)
School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand
e-mail: s.parsons@auckland.ac.nz
K. M. Borkin
e-mail: k.borkin@clear.net.nz
C. O’Donnell
Department of Conservation, Southern Regional Science Centre, P.O. Box 13049, Christchurch 8141,
New Zealand
e-mail: codonnell@doc.govt.nz
123
Biodivers Conserv (2011) 20:3537–3548
DOI 10.1007/s10531-011-0144-7