By David La Puma, Ph.D
Director, Cape May Bird Observatory
New Jersey Audubon
We’re in the midst of fall migration, in which masses of birds descend on our forests, farms, wetlands, lakes, and shores to find shelter and refuel for their journey further south or to hunker down and settle in for the winter.
To celebrate the spectacular migration phenomenon, the Cape May Bird Observatory recently hosted the longest-running birding festival in the country, aided by the shape of the Cape May Peninsula, which funnels birds into a smaller geographic area where they pause to rest and feed before crossing the Delaware Bay.
Fall is a time to not only revel in this phenomenon, but also to recognize the factors that affect birds on their breeding grounds and during their travels.
Birds face numerous threats, such as climate change and habitat loss. It is widely recognized that neotropical deforestation affects the populations of songbirds such as orioles, tanagers, warblers, and vireos.
Of course, significant habitat conversion also happens right here at home. For example, unsustainable land conversion to agriculture is occurring in the valuable prairie-wetland ecosystem known as the Prairie Pothole region, spanning across Montana, North Dakota, South Dakota, Minnesota, and Iowa, to produce corn ethanol to satisfy Renewable Fuel Standard targets.
While the federal Renewable Fuel Standard program began with good intentions to reduce greenhouse gas emissions and dependence on imported oil by requiring petroleum-based fuels to be supplemented with renewable plant-based fuels, it is now harming our nation’s wildlife and requires reform. While New Jersey is not a significant corn-producing state, the conversion of native prairie to produce corn ethanol stands to impact us nevertheless.
The Prairie Pothole Region is considered the most important breeding habitat in North America for waterfowl, including species that pass through or spend the winter in New Jersey, such as blue-winged teal, northern pintail, American black duck, and canvasback. Bands placed on birds’ legs help reveal migration patterns, and recoveries of banded birds in New Jersey have shown that blue-winged teals, American black ducks, and mallards are migrating from the Prairie Pothole and Great Lakes regions, connecting us to these landscapes that would otherwise seem distant to our mid-Atlantic coastal state.
These critical landscapes are undergoing massive alterations through draining and plowing, eliminating the unique, temporary wetlands resulting from glacial depressions that waterfowl use as breeding habitat. Between 2008 and 2012, more than 7 million acres of grassland and other habitats across the Midwest were converted to agriculture. In a two-year time span alone, 3.2 million of these acres were plowed and drained in the Prairie Pothole Region, in large part to meet demand for corn ethanol production. The nearly singular focus on corn as the main plant biofuel source used to meet Renewable Fuel Standard goals is extremely problematic. I lead tours to areas of the Midwest where the scale of this land conversion is staggering. Back home, migration is a reminder that we cannot allow this irreversible harm to unique prairie and wetland habitats known as our nation’s duck production factory to be “out of sight, out of mind.”
While many species observed during fall migration breed right here in the Garden State, during the spring and fall we are treated to sightings of species that only pass our way once or twice a year or whose numbers increase substantially during migration. The blue-winged teal is one such species. A small duck classified within the group that “dabbles” on the water’s surface by tipping its head down to feed and leaving its bottom exposed, this species is most easily identified by the striking white crescent moon pattern on the face of the male. (Although it is the more difficult-to-observe patch of blue feathers on the upper wing that give the species its name.) The blue-winged teal is a long-distance migrant that breeds in small pockets in northern and southern New Jersey but in much larger numbers across large portions of the central US and Canada, with the Prairie Pothole Region being particularly important. And while many species are more rare or unusual, and thus actively pursued by birders, this is one species we should strive to keep abundant by helping to eliminate significant loss of its breeding habitat.
Migration spectacles depend on volume. It is not easy to find a trickle of birds across a large landscape. The mass movements of birds through Cape May not only allow for the enjoyment of festival-goers but also for significant data collection. Take for example, the Avalon Seawatch, which New Jersey Audubon’s Cape May Bird Observatory has been conducting since 1993. Each year between September 22 and December 22, we tally upwards of 800,000 migrating waterbirds, including ducks, gannets, cormorants, and more. The majority of this count is made up of ducks. Imagine seeing nearly 70,000 black scoters streaming past Avalon (October 26, 2007, record) or more than 13,000 red-throated loons passing by (November 24, 2015, record). This gives us significant insight to bird populations.
Birdwatchers, hunters, conservationists, and frankly all New Jersey citizens that enjoy the sight of ducks dabbling or diving on their local shores, lakes, and ponds should encourage reform of the Renewable Fuel Standard. This doesn’t mean the abandonment of biofuel goals, but limiting the share of ethanol made from corn to meet renewable fuel targets is one place to start.
Letting your Congressional members know that you support efforts to limit native prairie and wetland habitat destruction for the Renewable Fuel Standard is one great way to help maintain the spectacular migration season we enjoy in New Jersey.
About the Author
Out There With the Birds is the official blog of Bird Watcher's Digest, featuring engaging content, commentary, and creativity from some exciting new voices. New posts appear several times a week, so please check back often!