Tag: grassland bird survey

by Meaghan Lyon, Wildlife Biologist

Each year since 2017, CWF has been teaming up with partners from the USFWS New Jersey Field Office to survey the JB McGuire Airfield for grassland birds during the breeding season.  Part of a long-term monitoring project, the airfield has been undergoing habitat restoration to maintain native warm season grassland habitat. The habitat restoration efforts are nearly 70% complete with roughly 700 acres seeded since 2017 and another 100 acres to be completed the following year.

Six of the ground-nesting bird species documented at the airfield are State-listed as either endangered, threatened, or of special concern.  The eastern meadowlark (Sternella magna), a member of the blackbird family, is a State Species of Concern.  It prefers a minimum of ten to twenty acres of unfragmented dense grasses of medium height for nesting.  The State-threatened grasshopper sparrow (Ammodramus savannarum) favors patches over 100 acres containing short- to medium-height bunch grasses interspersed with patches of bare ground, a shallow litter layer and scattered forbs. The savannah sparrow (Passerculus sandwichensis), also State-threatened, requires a mix of short and tall grasses, a thick litter layer, dense ground vegetation, and scattered forbs.  Another member of the blackbird family is the State-threatened bobolink (Dolichonyx oryzivorus).  Bobolinks prefer to place their nests in areas of greatest vegetative height and density and could potentially nest in patches as small as five to ten acres.  The State-threatened horned lark (Erimophila alpestrias) nests in areas of barren ground with short and sparse cover and are quick to abandon sites as vegetation grows thicker. 

Continue reading “2023 JB McGuire Grassland Bird Survey”

by Meaghan Lyon

Earlier this week CWF and USFWS biologists joined forces to start off the season with a grassland bird survey in Burlington County, New Jersey. The vast grassland habitat, doubling as an airfield, is home to the state endangered upland sandpiper, state threatened grasshopper sparrow, savannah sparrow, and bobolink, as well as the eastern meadowlark, a species of concern. These bird species, among many others, can all be found nesting at this site in the clumps of grass during the months of May, June, and July. Many of the management practices at the airfield, like consistent mowing, help maintain this grassland habitat and keep it an early successional state for grassland birds to nest in year after year.

For the survey, biologist met on site just before sunrise with binoculars hanging from their necks and clipboards with data sheets in hand. Male birds were already perching on tall blades of grass and singing to attract mates and defend territory as we dispersed to our survey points. At each point it was our job to distinguish what bird song and calls we were hearing and record any focal species activity onto our data sheets.

Between the three surveyors and 25 survey points, all of the target species were identified as well as hundreds of red-winged black birds, two great egrets, and a few mallard ducks. Of particular note, one upland sandpiper pair was sighted in its usual nesting area.

Three more surveys will follow between now and the end of the grassland bird nesting season. Follow along for updates throughout the season!