Songbird Conservation Issues Wood thrush Forest fragmentation Increases

Songbird Conservation Issues Wood thrush

Forest fragmentation… • Increases predation – more “edge” • Reduces deep-forest habitat • Increases cowbirds’ access to nests

Cowbird brood parasitism • Cowbirds lay their eggs in the nests of other, usually smaller, species • Sometimes they eject the host’s eggs • Cowbird eggs often hatch earlier than host eggs… Male cowbird Prothonotary warbler nest

• Host feeds cowbird at expense of its own chicks • Heavily parasitized species decline in population • Recent research shows that cowbirds monitor nests, and punish birds that remove cowbird eggs by destroying the host species’ eggs • They even destroy some nests, so the birds have to rebuild – the cowbird can then time their egg-laying to match the host bird’s • Many host species can’t distinguish between eggs, or count Warbler with cowbird chick Reed warbler feeds a cuckoo

Tropical deforestation Many of our local, summer birds spend the winter in tropical forests that are vulnerable to logging – forests are being converted for farming, grazing, mining and timber operations

Climate change • Migrating birds are getting “out of synch” with their insect prey • Climate zones in U. S. are shifting northward – preserved land may not provide habitat it originally protected

Shifting habitats – two different models

Two models’ predictions about the future climate in Illinois:

Hazards of migration • Natural hazards: bad weather and predation • Collision with tall structures – buildings, utility poles and power lines, wind turbines… • Habitat loss at resting/refueling stopover sites

Some species undergoing population declines: Wood thrush Cerulean warbler Eastern wood-pewee Olive-sided flycatcher