Confirmed breeding pairs of Kentucky Warblers at Baldpate Mountain went from ten in 2011 to three in 2012, the year the Eastern Chipmunk population exploded on the north side of the mountain. Kentucky Warblers did not breed in previous strongholds along the Ridge Trail and the Northwest Red Trail in 2012 but still bred on the southern slope. That year a decrease in Red Fox sightings was observed on Baldpate and on adjacent properties. In the following two years, Barred Owls were heard by multiple observers during their breeding season on the north side of Baldpate, where they were attracted to an abundance of their favored prey. A Kentucky Warbler pair was confirmed breeding in 2015 on the periphery of an old territory. A decrease in foxes led to an explosion of their prey, Eastern Chipmunks, which led to a decrease in a ground-nesting bird, Kentucky Warbler – a classic trophic cascade. Eventually, the proliferation of chipmunks attracted a second predator, the Barred Owl. Keep enough pieces and the web of life is resilient. Checks and balances maintain a healthy biodiversity.
Keeping all the pieces is the key to successful conservation. In nature everything is connected to everything else. The more we ensure connections between species, the more resilient the ecosystem. In the example above, two of the species are in trouble. The New Jersey threatened Barred Owl requires a large expanse of wooded habitat. Breeding territories can be as large as two square miles. The ground-nesting Kentucky Warbler, an Audubon Watch List species and New Jersey species of conservation concern, is an interior forest-breeding species, requiring well vegetated understory and ground layers within the interior forest. Kentucky Warblers need a specialized habitat within a specialized habitat to successfully breed. Both species are highly sensitive to forest disturbance.
Baldpate Mountain’s strength is its native plants, a healthy assortment of native canopy trees, four large areas of high quality Spicebush understory, and areas with native groundcover. Baldpate is not pristine, but where the native plants are dominant, native wildlife thrives. Baldpate’s weakness is its size and shape. Its area is at the lower limit for a viable interior forest ecosystem, and the long, narrow shape enhances the edge effect, making the Baldpate ecosystem highly vulnerable to habitat loss, fragmentation and degradation. This is why the proposed PennEast pipeline will have a devastating effect on Baldpate’s biodiversity.
Baldpate is perhaps the most fragile of the Important Bird Areas and other preserved lands threatened by PennEast, but fragmentation and degradation of habitats will have a negative effect on biodiversity along the entire route. Pieces will be lost, connections will be broken, and resilience will be lost.