Thursday, November 10, 2016

Nest-site Selection by Pennsylvania Broadwings

On October 19th, Rebecca presented at the 50th Anniversary Raptor Research Foundation Conference in Cape May, New Jersey on the results from our study looking at the habitat or land cover surrounding Broad-winged Hawk nests in Pennsylvania. 
HMS former trainees and staff at the 2016 RRF Conference in Cape May, NJ

This work expanded on our original project findings based on 19 nests for 2014-2015, used in Rebecca's Master's thesis, to include nest sites from 2016 and those identified in the 2nd Pennsylvania Breeding Bird Atlas (Wilson et al. 2012). The purpose it to try to figure out if Broadwings are selecting certain habitat features or types of forest for their nests.




Yellow blocks= areas where BWHA nests were found in the 80's but were not found again in 00's



Dark red and dark blue dots= BWHA nest sites AND lighter red and blue dots are the available sites where BWHAs were not confirmed (also known as "random sites")



Average land cover composition of 60 BWHA nests in Pennsylvania. Over 79% average total forest cover surrounding 1km of BWHA nests

We wanted to compare confirmed nest sites with available "random" sites. Available sites were randomly selected at a range of distances from 2km to 10km and 10km to 20km from nest sites
Nest and Available sites selected in areas where there was less than 60% deciduous forest cover surrounding 1km of sites

Nest and Available sites selected in areas where there was greater than 60% deciduous forest cover surrounding 1km of sites


Habitat use composition of 9 female Broadwings on their breeding grounds, during the months of June-August
Map (left) with 85 roost sites of 9 tagged Broadwings plotted in ArcGIS