Saturday, January 25, 2020

The Top Threats to NJ Birds, and What We Can Do About Them

[Above, Scarlet Tanager, Ken Lockwood gorge, NJ. Below, Wood Thrush, High Point State Park, NJ. Two forest-nesting neotropical migrants to be thinking about. Not all news is dire; these two are both still relatively common. Once more: the time to save species is while they are still common.]

We want lots of birds of lots of species. How do we achieve that end?

It is important note that here I speak of NJ specifically. What happens in North America or worldwide generally does not necessarily apply to NJ, although it often does.
Here are the horsemen, the top threats to birds here IMHO, and some ideas on what we might do to stop them:

1. Habitat loss.  There is good news, in that much of what is not hardscaped in NJ is already preserved in one way or another. But not all.

What we can do: Start locally by supporting the land-protecting organizations and agencies near where you live or like to bird. My favorites include the Hunterdon Land Trust alliance and, in southern NJ, the Natural Lands Trust, but I applaud them all. Making sure the state Green Acres program is always funded is essential to these and other organizations, as well as state agencies like the NJ Division of Fish and Wildlife, the state Park Service, and the state Forest Service. I am not specifically calling out the many wonderful “Friends of” groups, like the friends groups attached to our federal National Wildlife Refuges (Wallkill River, Great Swamp, Edwin B. Forsythe, Supawna Meadows, and Cape May NWR’s) or other friends groups, like Friends of Liberty State Park, simply because these organizations are not specifically focused on protecting land by acquiring it. But I just did call them out, didn’t I? For a group with a broader brush, the Nature Conservancy is always a good bet. Support the federal land and water conservation programs. Contribute your time, knowledge, votes and money.

It is important to note that not all protected land is created equal, which leads us to threat #2.

2. Habitat degradation.

[Above, Kentucky Warblers require dense understory for nesting. Below, Prothonotary Warbler, Peterson's "golden bird of wooded swamps."]

Even protected lands usually need help. Threats include invasive exotic plant species, often aided and abetted by overabundant white-tailed deer.

What we can do: Remove invasive plants. Simple, no? No is right: not simple, not easy, but very important. Every landscape is different and may require a different approach. You can pull exotics, but that may disturb the soil and invite new exotics. For example, pull Japanese Barberry with a weed wrench, which works, but you invite Garlic Mustard. Pull Garlic Mustard, and invite Japanese Stiltgrass. Cut forest to create early successional habitat and invite everything unless you have a long-term invasives management plan in place and funded.

You can use herbicides, and then introduce toxins to the environment. An example is treatment of Phragmites, a.k.a. common reed. As far as I know, the only two ways to deal with phrag are herbicides or inundation with salt water. Repeated mowing during the growing season may work, but what a nightmare of work and money. Herbicides like glyphosate (trade names Round-Up or Rodeo for aquatic applications) kill aquatic invertebrates and are emerging as human health threats, AND it seems clear you can’t achieve long-term control of phrag without annual spraying, and maybe not at all for old growth phrag. Saltwater flooding works, think the east pool at Forsythe NWR or, if you are familiar with it, the marsh at Cox Hall Creek in Cape May County. The trouble with saltwater flooding is that you wind up with saltmarsh, a very different habitat with very different biota than freshwater marsh. Like no amphibians and no freshwater marsh birds. I have been half-joking for years that one way to deal with phrag would be dynamite. If we blew large holes in a phrag marsh, we would create open water pools amidst otherwise dense reed, which would be better for frogs, turtles, freshwater fishes, and marsh birds. We could get the military involved, maybe bombing runs from planes. . .or we could use excavating equipment.

On deer: I love deer, and we are fortunate we have one large mammal that puts up with us. Two, actually, the other being black bear. Deer were at one point all but eliminated from NJ, reintroduced, protected, encouraged, and they exploded in numbers. Now the pendulum of hunting regulations has swung back, and there are lots of places where there are no longer too many deer, which I would suggest is perhaps 20 per square mile or less depending on the habitat. In places where there is little or no deer hunting pressure, there are too many, sometimes way, way too many. The fix is easy, and the resistance is a loud paper tiger. Where there are too many deer, we have to kill them.  Ask Great Swamp NWR. Ask Duke Farms.

The Morristown National Historic Park/Scherman-Hoffman Wildlife Sanctuary complex is the poster child for the deer problem. Once at a meeting I listened to Dr. Emile DeVito go off on this. Emile said the whole place was going to become a savannah, not a forest. And he's right if nothing is done, a savannah of falling trees with no regeneration, no native shrubs or wildflowers, a sea of Japanese  Barberry, garlic mustard, Japanese stiltgrass, a sea with Asiatic earthworms swimming underneath. Make me god and I'll start the fix. The deer must be clearcut. If the National Park lacks the power or political will, partner with the NJ Division of Fish and Wildlife and hunting organizations and organize a "saturation hunt" on every private land in the area that you can. Require the hunters to bait the area they will hunt to pull deer off the park, to use treestands, and yes, to use guns. Close the area to the public for two weeks of hunting in December or January. Work with local law-enforcement agencies, and if people want to protest, give them a place and hire off-duty officers to keep order. Require the hunters to shoot a doe for every buck. Let them keep what deer they can consume, and donate the remaining venison to food banks. Ask the hunters to pay for the venison processing, the only fee they must pay. Do this year after year. Invite local school children to make "seed bombs," dirt packets containing seeds of native trees, shrubs and wildflowers, and send them out to throw or plant them. Don't worry about wind-borne seeds, there's plenty of them. Figure out the best ways to deal with the invasive plants and worms and get on it. This complex used to have nesting Ruffed Grouse, Kentucky Warblers, Cerulean Warblers, Acadian Flycatchers, thrushes, Pink Lady's Slippers. The people deserve that back, and so do the birds.

One more thought on habitat degradation: what about farms? Are they good for birds? If you pay taxes, you have paid into farmland preservation programs, which in NJ often involve buying easements on farmlands at a cost slightly less than fee simple purchase. The owner keeps the farm, the public can't go there, and the habitat becomes whatever the farmer wants, pretty much. Is this good? I am biased towards farms, I grew up on a farm and had relatives who farmed, and I know firsthand how hard that work is. Farms are beautiful, but again, are they good for birds and other wildlife? Better than hardscape, certainly, but I am aware of one NJ preserved farm that grows greenhouses and mines the ground water. Better than suburban lawnscapes? Probably, but I lived near one of the last nesting sites in the Amwell Valley for Upland Sandpipers, and when that farm was preserved the habitat was shifted from pasture to a variety of row crops, and the uppies were no longer there. Are we good with that? I don't have a firm answer, but the question deserves thought.

3. Sea Level Rise.

[Above and below, Clapper Rail adult and chick. Rails swim very well, even the chicks. Eggs, however, don't swim, and rails eat stuff that lives in tidal marsh, like fiddler crabs.]

[Saltmarsh Sparrow, still a common breeder in NJ high marsh. What happens to this species when there is no longer high marsh? They will disappear.]

The sea level worldwide is rising, incontrovertibly, and unfortunately it is rising faster in NJ than many other places due to subsidence. 18" in the last century. Between 7 and 16 more inches by 2030. That's not my data, it's from Rutgers University:

What does this mean to birds? Nothing but bad. Saltmarsh nesting birds like Northern Harrier and Black Rail are already all but gone from NJ. Saltmarsh Sparrow will be next, even the still wildly abundant Clapper Rail faces doom. Do yourself a favor and go kayaking in a coastal system, or get on one of the wildlife tour boats, during a June or July full moon high tide. What a scene! Clapper Rail families swimming about. Laughing Gulls sitting on nests being carried away by the tide.

Who else is sea level rise going to get? Beach-nesting birds, already in a bad way, though they have the "advantage" of beach dredge and fill operations brining more sand onshore every year, which nature reshuffles every fall and winter and so moves some of it to where beachnesters are. Migrating shorebirds that feed on tidal flats will lose tidal flats to feed on. Shorebirds feeding on horseshoe crab eggs on Delaware Bay will lose beaches and probably crabs.

What we can do: Not a blessed thing. That cow is out of the barn and IMHO it's too late to shut the barn door. Yes, saltmarsh may accrete as sea level rises. Yes, we can try thin-layer deposition on marshes to build them up. And yes, yes, and yes, we can and should do everything we can to minimize the climate change at the root of the problem. I try not to be glum, but we're too late for even our children and I'm down to thinking in geologic timescales. I imagine Edwin B. Forsythe NWR's 40,000 acres of marsh becoming a shallow bay. And I know I'm supposed to be writing about birds, but if you like to saltwater fish, the inshore fishery is hugely dependent on the tidal ecosystem. I hope I'm wrong.

Up next: more dishonorable mentions. Non-point source pollution. Habitat succession. Predators, human-subsidized and otherwise. And then, who the hek am I to be writing this stuff, and why I am.

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