A thwack in the park

I spent the fall of 2017 and winter of 2018 thwacking my way through the refuge’s brushy young forests. Blackberry brambles snagging my thick Carhartt coveralls and grabbing my every limb made progress slow. Gnarly stumps lay their own obstacle course at my feet. Ducking below and around bare thin branches, I tried to spare my rosy red cheeks and face from the poking and scratching that threatened the only parts of me exposed in the cold, crisp air. My task: to evaluate each field and determine its fate — would it be cut this year, or would it remain?

No wonder the woodcock love this stuff, I thought. This is a miserable place to be a large mammal. Opposable thumbs aside, I can’t imagine it’s much easier for a fox or a coyote to make its way through here.

A woodcock. Carlos Guindon/USFWS

I envision what it must be like for a woodcock to wander through this brush, navigating their way through stems spaced like agility pegs and horse jumps. A canopy of branches is layered above. Dense leaves hide the sky from the woodcock’s upward-looking and predator-leery eyes. The moist earth, protected from the sun’s evaporative rays by leaves above and underfoot, is chock full of earthworms who erroneously think THEY are protected by all this bramble. Not to be outsmarted, the woodcock have developed a graceful dance — a sort of forward-stepping, vertical bobbing motion — to detect the earthworm’s nearly imperceptible underground presence. Shielded by all that’s above, the woodcock must feel that this is the perfect place to build their ground nests and raise their fluffy young.

So if these brushy fields are so good for the woodcock, you might ask: why was it my task to evaluate them for cutting? To answer that, we turn to the US Fish and Wildlife Service’s Migratory Birds program, and the annual surveys that they’ve been conducting — one that the refuge participates in annually — since 1968.

Average number of woodcock heard on annual survey routes across the Eastern region, 1968–2018. Graph from Seamans and Rau 2018 (American Woodcock Population Status, 2018. USFWS, Laurel, MD.).

Each spring, States and National Wildlife Refuges alike send volunteers and staff out to listen for singing males on 1,000 woodcock survey routes across the species range. Following a standardized protocol, this cooperative data is submitted annually to the Division of Migratory Bird Management at Patuxent Research Refuge in Laurel, Maryland. Once compiled, the data is used to monitor the rangewide population and then to set annual harvest limits at the federal level. This long-term dataset shows that the woodcock population has been in steady decline since surveys began. And the primary reason for their decline? Habitat loss.

Photo by Peter Smithson

You see, woodcock depend on the brushlands for rearing their young from ground nests. The protection it offers from mammalian and avian predators, and the rich earthworms that can be found there, make it prime real estate. But brushlands themselves are a short-lived phenomenon, and around Great Swamp NWR they can attain forest character (with trees dominating and shading out the ground layer) in as little as 10 years. Across the east, nearly 13 million acres of scrubby brushland habitats have been lost either to suburban development or to forest conversion since the 1960’s, and with it go the woodcock. Here in the northeast, mature forests seem to have captured the heart of the average suburbanite as sign of a healthy bit of nature left to be — and scrubby brushlands can be perceived as an interim mess, no longer pretty or useful to us. Beauty is, of course, in the eye of the beholder. For the woodcock, the loss of brushlands has been an ugly thing.

And so, odd as it sounds, the only way to maintain these ephemeral habitats is…to cut them down. By cutting early successional (“young”) habitats in rotation, staggered from year to year and field by field, the refuge is able to consistently maintain suitable habitat for our woodcock friends. And as much as our brushlands love to grow up into forest, they are equally eager to regenerate following cuts — often growing back even thicker than they started. In as little as 6 months those fields will be dense with vegetation 5–6 feet tall, eagerly sprouting upward and outward.

Woodcock dance. Keith Ramos/USFWS

And the woodcock happen to love hanging out in those really thick brushlands, even if I do not.

Marilyn Kitchell is the biologist at Great Swamp National Wildlife Refuge in New Jersey.

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