Bat Ecology Flashcards
What does PEA stand for?
Preliminary Ecology Appraisal (for bats)
What is a suitability assessment based on?
Habitat features only - e.g. the presence of a roost would not automatically make the suitability class as ‘high’
What can potential suitability of a proposed development site for bats range from?
None, negligible, low, moderate, high
What are the tree suitability classifications called, and what do they mean?
“None” (either no PRFs or highly unlikely to be any); “FAR” (Further Assessment Required); PRF (a tree with at least one Potential Roost Feature)
What is an endoscope and what is it used for?
An endoscope is a long, thing tube with a small camera inside. Lightweight endoscopes are ideal for investigating burrows, nest sites etc
What does GLTA stand for?
Ground Level Tree Assessment
What does PRF stand for?
Potential Roost Feature
What are bat activity surveys?
Observation and acoustic (manual or static) surveys using bat detectors to establish species and measure bat activity
What does ALBST stand for?
Advanced Licence Bat Survey Techniques
Do you need to consider impacts on bats even when trees are retained?
Yes
What is a the typical bat survey process?
- Ground Level Assessment - PRFs not always visible from the ground so results at this stage are approximate; 2. Roost feature inspection surveys, to asses roosting resource; 3. activity surveys, to help understand what species are on site
What does NVA stand for?
Night Vision Aids
Are transect surveys manual or automatic?
Manual
What do automatic/static bat activity surveys involve?
Installing bat detectors at fixed locations to record bat activity remotely
How many UK bat species use trees for either foraging and/or roosting?
All of them
Talk through bat activities over the course of a year/bat calendar:
Over winter bats hibernate in caves, cellars etc. March: come out of hibernation, feed on warmer nights. April: Females move to maternity roosts. May: Ideal time to start surveys - pregnant females in maternity roosts. June/July: Bats have their young. August: Young start to fly and feed. September/October: mating and swarming. November: Start to go into hibernation
What are day and night roosts?
Simply where bats go in the day and night, especially if they’re out foraging and the weather gets bad
What is a feeding roost?
Where they go to feed. You may see butterfly, moth etc winds there (they eat insect bodies but not wings)
What is a transitional roost?
Roosts that bats use between summer and hibernation roosts.
What is a maternity roost?
Where bats go to breed
What is a hibernation roost?
Where bats go in winter months to hibernate
What is a satellite roost?
A roost that’s used in conjunction with a main bat roost (e.g. a maternity roost)
What are the most important roost types?
Most important: maternity. Second most important: Hibernation
What are some key reasons why bats leave roosts?
Disturbance (bats are very fussy e.g. if you take a tree away that provides shading to a roost then they may leave it); predators e.g. barn owls; infestation of an insect they don’t like e.g. hornets
Do bats ever return to roosts once abandonded?
Yes, sometimes they do
When are bat activity surveys undertaken?
Summer
What are the main threats to bats?
Agricultural intensification, habitat loss and fragmentation, loss of roost sites from development etc, and climate change
What is a bat roost? (general definition)
Any place that bats use to find refuge and/or shelter
Do bats switch roosts?
Yes, some switch often - e.g. some use up to 60 roosts a year
What order are bat tree surveys undertaken in, and when?
Walkover surveys to identify features are ideally undertaken first in winter. Climbing surveys for trees requiring work with PRFs identified may then be undertaken. Bat activity surveys should be undertaken in summer. June/July is a really good time to survey as bats should be back in their summer and maternity roosts
Will ecologists look at buildings e.g. houses when surveying a rural site?
They may do - it’s worth checking with them and notifying the landowner(s) if they are
