“April Come She Will”

With pictures of summer field work adorning my cubicle walls to guide the way, I hunker down in my office planning away for projects to come.

Since returning from Herbarium work in Anchorage, I have been mostly planning for the busy field season ahead.  On our plate we have:

  • Continued surveys of invasive plant species
  • Soil surveys to be conducted at the end of July
  • Raptor surveys
  • A newly funded Little Brown Bat (Myotis lucifugus) inventory and monitoring project

Much of my end of preparations for raptor surveys has been completed.  These surveys will involve my supervisor and the other office biologist flying along river corridors in the Fortymile region of the interior, in search of raptor nest sites and raptors themselves (hopefully I will be able to get in on a trip). Raptors in this area include: Peregrine Falcons (Falco peregrinus), Gyrfalcons (Falco rusticolus), Bald Eagles (Haliaeetus leucocephalus) and Golden Eagles (Aquila chrysaetos).  I spent some time this fall using ArcGIS to identify suitable cliff nesting raptor habitat.  This involved looking at lots of aerial imagery, and creating GIS layers that might be predictive of cliff areas when aerial imagery was poor or missing (ex. slope, extracting ‘bare’ portions of vegetation layers).  Our wildlife biologist is quite experienced at this and gave me some tips on spotting appropriate landmarks from aerial imagery.  The aerial imagery method is very effective but time consuming and requires experience and practice.  Although it is certainly less selective, I developed some GIS layers that can hopefully help when large areas need to be scanned or can be combined with aerial imagery to make better predictions.

Capture

Aerial imagery showing a portion of the Fortymile river. Red dots mark habitat of varying potential with that bright white curve in the upper middle being prime cliff habitat.

raptor

Layer showing land designated as ‘bare’ in vegetation surveys. Does a decent job at pulling out the barren cliff faces.

slope

Layer showing slope (red is steeper). Identifies steep portions of the landscape which, in junction with the bare layer, can help pinpoint cliffs.

 

The main project, however, will be bat inventory and monitoring.  I’ll be handling most of the planning/logistics/equipment/study design/field work so although it’s not plant related, it should be a good experience in planning and executing a study.

Little brown bats are the most widespread in North America and one of the only bat species found in the Alaskan interior.  Very little is known about their habitats/distribution/behavior in this area, however, and with rising concerns about white-nose syndrome folks are eager to find out more.

Our first study area will be the Steese National Conservation Area about 70 miles NE of Fairbanks.  It is an interesting study area for bats because 1) it is northerly: bats are nocturnal and the latitude of this location means it gets VERY little darkness during the summer months—civil twilight persists for the majority of the summer with no true darkness and near the solstice there are only about 1-1.5 hours of darkness a night AND 2) it is cold: some research has predicted that 5 degrees Celsius might be the lower limit for some bat activity—nightly summer temperatures in this area could easily dip below this.  Scandinavian studies have found bats at latitudes up to 69N (above the Arctic Circle where the sun doesn’t set for some stretches of summer) with observations that bats will operate when ambient light levels are lowest (even though prey availability is lower at these hours).

For this first season of the study we are mainly testing field schedule/equipment/methodology and trying to see if we can even find bats in this area at all.  The plan is to procure 10 acoustic bat detectors and place them in strategic areas (likely bat habitat) in the SNCA, returning every 3 weeks or so to switch out batteries/download data and move detectors.  We are hoping to capture information on bat arrival and departure, seasonal changes in bat activity, nightly changes in bat activity and preferred bat habitat.  With smart placement of detectors we will hopefully be able to find some bats and pilot study designs that later down the road will provide more robust data on bat habitat preferences.

far

A typical acoustic monitoring set-up from a partner agency’s bat monitoring protocol. The detector itself is strapped to the tree in the foreground and the microphone can be seen mounted to a tall pole in the background.

Right now my computer screen is an explosion of tabs for 12V battery brands, PVC pipe, bat detector prices, occupancy modeling studies, battery physics tutorials etc.  Working out lots of logistics for deploying these expensive pieces of equipment in remote areas.

Katie

Fairbanks, AK

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