The Barn Owl Project

The Barn Owl Project

The New Jersey Barn Owl population is on a steep decline

Why It Matters

Barn owls (Tyto alba) are globally widespread, found on all continents except Antarctica. Their numbers in New Jersey, however, are in steep decline. Barn owls depend on open grasslands that support small rodents, and they require secondary cavities for nesting (meaning they can’t make their own cavity). The downward population trend in New Jersey is associated with urban sprawl, development of former agricultural lands, and agricultural changes from dairy farms to row crops (Colvin et. at. 2019). Another threat to barn owls is exposure to poisons and pesticides targeting their prey. The population of barn owls in the interior areas of New Jersey has plummeted as their foraging areas continue to disappear. The stronghold in New Jersey has become the coastal wetlands population, where the habitat provides better long-term availability of foraging habitat and prey (Colvin et. al. 2019).

Research has shown that unfortunately, this coastal population is also experiencing a decline. The Barn Owl Research Foundation has been studying the barn owl population in southwestern New Jersey for 40 years. Their barn owl boxes, located near coastal wetlands along the Delaware Bay and River in Cumberland and Salem counties have been closely monitored since 1980. Although barn owl populations naturally fluctuate year to year, related to weather conditions and prey availability, numbers have been showing a steady decline (Colvin et. al. 2019). The number of nests in the study site has declined from 36 nests to 11 nests just over the last 10 years. The 2019 season showed a high population turnover, a record low number of nests, smaller brood sizes, and higher chick mortality rates (mostly starvation). This trend is likely associated with increased coastal flooding and higher tides affecting the prey source (Colvin et. al. 2019). The fate of barn owls is therefore closely linked to climate change.

Conservation Efforts

The two factors necessary for the conservation of barn owls are the conservation of good foraging habitat and the use of properly designed and installed boxes in those areas (Colvin et. at. 2019).

Conserve Wildlife Foundation is launching a coastal Barn Owl Box Project in Winter 2020-21 along the salt marshes of the Atlantic coast. We are using the box design that has been proven successful by the Barn Owl Research Foundation and installing boxes in areas of suitable foraging habitat. Only a handful of barn owl boxes have been placed along the Atlantic coast in comparison with the extensive number of boxes along the west coast of the state. With a seemingly vast amount of habitat, the limiting factor for the barn owl population here may be nesting cavities. Installing boxes will also make monitoring easier since barn owls will typically shift to a nearby box from alternative sites such as tree cavities (Colvin et. al. 2019).CWF will initiate our work in Cape May County, and some of the first sites will be those where barn owls have been documented. The boxes will be monitored for nesting success and owlets will be banded. We are also seeking to install a Barn Owl Cam at one nesting site in order to study the owls’ behavior without disturbance and to provide the public with an opportunity to experience an up-close view of these charismatic creatures. Stay tuned for updates on this exciting new project!