Wednesday, February 12, 2020

Threats to NJ Birds: the Next Three Dishonorable Mentions

We want lots of birds of lots of species. How do we achieve that end? Here are three more top threats, and what we can do about them. (Previous blogs on this thread were on January 5, January 17, and January 25, 2020, find them by clicking on the main banner above and then scrolling down, or under "Time Machine" at right, depending on how you're viewing this).

[Above and two below: Least Bittern, Pied-billed Grebes, two species affected by non-point source pollution of fresh water. Click to enlarge all photos.]


4. Non-point-source pollution. Non-point-source pollution has been a major problem for this country and around the world for a long, long time. This is pollution that essentially comes from everywhere, not the end of a pipe. So run-off from developments, roads, agricultural areas, all of which can carry toxins, salts, and fertilizing substances like sewage from septic systems and straight nitrogen, phosphorus, and potassium from fertilizers. Non-point source pollution also includes exhaust from fossil-fuel-burning things like cars, trucks, and woodstoves, though we're not dealing with air pollution, acid rain and climate change here.

Non-point-source-pollution screws up water quality. It can make water bodies poisonous, or overly fertile, creating plant and algal blooms, which then can increase biological oxygen demand, which then reduces oxygen levels, kills fish, amphibian larvae, and aquatic insects (all a.k.a. bird food). It can kill aquatic plants, like the eelgrass beds of Barnegat Bay, which are or were fish habitat and food for birds like Atlantic Brant and Canvasbacks. Point- and non-point source pollution created a low-oxygen dead zone in the lower Delaware River that persisted into the 1970's and was all but impenetrable to anadromous shad, herring and striped bass. Non-point-source pollution turned the Kearney Marsh from a prairie-pothole-like system replete with breeding marsh birds into a toxic soup that seems to be a shadow of its former self.

[Organizations like the USFWS and Ducks Unlimited have made yeoman efforts to restore breeding habitat for Canvasbacks, yet the "king of ducks" has not rebounded to the huge  eastern numbers of the market gunning days. Why? Non-point-source pollution of coastal systems like Chesapeake and Barnegat Bays.]

What we can do:

Get rid of the current federal administration. What is being done by this administration to roll back clean water protections is all over the media. It's awful, appalling, learn from the past or you are doomed to repeat it, however you want to say it. We are fortunate in NJ in that we have some pretty great state-level water, wetland, and stream laws, and we must make sure these stay in place and are enforced. Other states also have good laws, and still more are developing them, I read some hopeful things about NC and VA today in that regard. But we must get this administration gone.

And here's a thing, and I've tweeted about this (@FreidayBird): water quality declines hurt people who like to fish and hunt (often leaning republican) as much as they hurt birds and birders. Like trout? They are the bellwethers of freshwater quality or the lack thereof. Fish for striped bass? Where are they going to spawn if the Chesapeake Bay and Delaware estuary reverse course in water quality? Like other inshore saltwater fish? When I was a lad, I'd fish Barnegat Bay out of Waretown with a seasoned boat captain named Percy Guiddes, and the catches of winter flounder, summer flounder (fluke) and others were just ridiculous, like 130+ winter flounder in one half-day trip, or 70+ fluke, for four fishermen and women. You can't make those catches anymore, not because of current strict regulations, and not (I believe) because the resource was overfished. It's because the fish aren't there, and although flounder can lay many thousands of eggs, what good is it if the babies don't grow up because water quality sucks? Enjoy duck hunting? Etc.

Go for chemical-free lawns. Fix your car if it leaks oil. Maintain your septic system if you have one. Seem obvious.

Use best management practices in agriculture and everywhere else next to water. Leave stream and wetland buffers, keep cattle out of streams. There are federal programs in place to help pay for this.

5. Ecological succession. I guess.

[Golden-winged. . .er, Blue w. . . er . . . Lawrence's Warbler, the rare backcross hybrid between Blue-winged Warbler and Golden-winged Warbler. This was at a site in Sussex County near the Delaware that used to have pure Golden-winged Warblers; it now has only Blue-winged Warblers.]

Ecological succession is a wonderful, fascinating process. Make a field and plow it (or have a volcano or earthquake), do nothing and you will get a more less orderly series of habitat changes from grassland to flowery meadow to scattered trees and shrubs (known as scrub-shrub) to young forest to old forest to what used to be referred to as climax forest, a term that is not so much in vogue because change is the only constant, trees fall down, storms knock a bunch down, fires burn landscapes down.

Let's ruffle some feathers: is creating or maintaining grasslands the highest and best use of an NJ landscape? Or should birders just go to the Dakotas, eastern Colorado, Nebraska and the like for their grassland bird fix? I'm not sure of the answer. I love grassland birds, many are in peril, and it's great not to have to travel to see them, and if you're a young or busy NJ birder maybe you can't. I'm not saying grassland is not a native NJ habitat, it is, but how important to conservation is an NJ grassland compared to NJ scrub/shrub or forest? Are NJ grasslands bird sinks, meaning overflow birds from other places wind up here, try to nest, but fail because the habitat is too small or inferior or there are too many predators or they get mowed too early?

Then there's scrub-shrub. There's a lot of talk in NJ about creating Golden-winged Warbler habitat. If that's the sole objective, you are wasting your time. There's a fair bit of GWWA habitat in NJ that is unoccupied. If habitat is unoccupied, then the problem is somewhere else, in the case of GWWA it's hybridization with Blue-winged Warbler, which it could be argued is nothing more than evolution in action, plus probably wintering habitat loss. In the 80's some predicted GWWA extinction by 2025.

However, there are a bunch of other species that like scrub-shrub: American Woodcock and Alder Flycatcher if it's wet, Prairie Warbler, towhees, catbirds, cardinals if it's dry, Chestnut-sided Warbler and Indigo Bunting if the edge between scrub-shrub and forest is sharp, not feathered, Ruffed Grouse once the scrub shrub gets a little taller. Some migrant forest songbirds when they are not breeding.

What we can do:

If we're going to have grassland areas, do it right. This means >100 contiguous acres, native grasses, and delayed mowing to allow the birds to nest, but birders must understand that asking a farmer to delay mowing hits their wallet by limiting the number of cuttings they can make, and reducing forage and financial value because late-harvested hay is less nutritious. In places like airports, there is no reason not to delay mowing and every reason to make grasslands, because they're not going to let trees grow there anyway and if you mow it flat, big, plane-crashing birds like geese, gulls and flocks of European Starlings like the short grass.

Maintain scrub-shrub carefully and thoughtfully. In particular, watch out for invasive plants, and consider the "edge effect" allowing predators and cowbirds better access to forest interior birds. Don't forget the NJ landscape is already pretty darn fragmented.

6. Predators, human-subsidized and not.

[At least this cat is after a non-native species.]

Thoughts about predators and predator control swing like a pendulum: they're killers, get rid of them; they're important and often keystone ecosystem members; they cause declines in already declining species; there are more than there should be because of humans; they are just so cool. All these thoughts have merit.

What We Can Do:

If predators have been artificially increased by humans, and are causing declines in bird populations, get rid of them. Domestic and feral cats seem like a no-brainer. Keep pet cats indoors, get rid of feral cats by adoption or lethal means. Harsh, maybe, but necessary. How about a state law mandating cats be kept indoors? Yes, I know, the political opposition . . .

Human subsidized native predators are trickier. Raccoons, skunks, opossums, Blue Jays, crows, eastern coyotes all are native, they belong here, but not as many as we've got. NJ red foxes may or may not be native, but feeding the ones on Island Beach for example is unhelpful to birds. Who decides how to play god? We do. I think eliminating predators where they are impacting endangered or threatened species is right. Control them at beach-nesting bird sites and grasslands. Certainly, don't encourage them. Proper sanitation practices help with the garbage pickers. Watch out for that edge effect.

[This lovely Upland Sandpiper egg at Atlantic City airport was not pipped open by a chick, it was predated on. Uppies are state-endangered; raccoons, foxes and skunks are not.]

There you go, my top-six picks for the problems NJ birds face. Are there others? Many, but we're doing ecological triage here, and also I am a pragmatist. One example: bird building strikes are a problem. NYC recently passed bird-friendly rules for construction, and that is terrific, kudos to all involved. The trouble is, the buildings are already there, and the rules apply to new construction and renovations. But again, it's great. Or consider lighted buildings and landscapes, which attract nocturnal migrants that sometimes circle them or hurl themselves into the glass. It is a problem, under certain weather conditions a big one, and there are better and worse ways to light things like transmission towers to protect birds. But please don't go to the police chiefs and mayors of Camden, Atlantic City, New Brunswick, Jersey City or Newark and say you're a birder and you think they should shut the lights off at night to protect the tweety birds. Camden or AC at night with no lights, hmmm. I mean, it might help with the human population problem, but we'll look like idiots. Yes, I'm being mildly sarcastic. Or bird road-kills. Bad, drive less, maybe there's some something someone could come up with to reduce them, but they don't make my top six.

Up next: ecological triage and why I feel compelled to spell this out. Warning: it will involve a little corporate-speak.

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