Tuesday, May 28, 2013

Keystone Species...

Brants fly in with the Rockaways in the background.
     On Sunday, May 26th, my husband and I went to Jamaica bay in hopes of seeing a keystone species to the Jamaica Bay ecosystem. Jamaica Bay is part of the Gateway National Recreation Area, and is a part of the Atlantic Flyway Zone - this means many migrating birds pass through there each spring and fall. Birds use Jamaica Bay as either a final destination in their migration or as a place to stop, fuel up, and continue on their journey. We were hoping to see one of these species, the red knot, a shore bird known for its dependence on the spawning of the horseshoe crabs.
     The horseshoe crab is what we call a keystone species, especially in this instance, the red knot among many shorebirds, relies on a feast of those little green eggs to put on some weight, enough to get them up into the Arctic where they breed and nest for the summer. I don't think we saw any red knots... most go to Delaware Bay, but a few do show up in Jamaica Bay. The ones that do come to Jamaica Bay, according to our guide, fly non-stop from Brazil - pretty amazing. Red knots have been declining in population, probably due to the over collection of horseshoe crabs which are caught and used as bait by fishermen. With less eggs to eat, if red knots cannot put on enough weight - they have to double their body weight - they cannot make it to the Arctic to breed. The horseshoe crab and its yearly spawning ritual is vital to the survival of many shorebirds in their journey to the North. This phenomenon makes the horseshoe crab a keystone species, its yearly ritual of coming ashore to spawn is vital to birds, fish, and turtles that rely on those millions and billions of eggs for nutrition. If the horseshoe crab disappears, it can be severely detrimental to the ecosystem. Think of a game of "Jenga," you can remove a bunch of pieces and it can stand, it will wobble but it still stands, but when you remove that one piece that doesn't budge, the one that when you "test tap" it, that is like your keystone species; you remove that piece and the many other species that are supported by it all fall apart.
     Enjoy what we saw down at Jamaica bay! And, if you are a shorebird nerd, please, help me try to ID some of these guys. Shorebirds are not my forte.

If you can figure out what these are, I can label them... I couldn't get a picture of them on the beach because the group I went with was never really kept together and people didn't really stay clear of the birds. After just having a talk with the guide about how these birds need to eat as much as they can, people didn't give them the space they needed to feel comfortable. Some serious birders looked highly upset, and I was fairly upset too. On the other hand though, I understand that this is a good opportunity for people to get out and discover nature, but I feel like there should have been more instruction by our guide on maintaining a respectful distance. So the only good photos I have are in-flight.
A male is lucky to have a female all to himself!
I guess being covered in sand is the equivalent to privacy... you had to be careful of where you stepped, crabs were all over.
Usually horseshoe crab mating is more like this, the larger female is surrounded by 3 smaller male crabs all trying to get on or around her, so they can hopefully be a dad. Horseshoe crabs have been around for 300 million years, and in that time, their body plan (the way they look) hasn't really changed. It is kind of cool to imagine this scenario happening 300 million years ago. And, remember, horseshoe crabs are not crabs, they are in the same group as spider, arachnids - crabs, like the ones we eat are crustaceans. All, though, are arthropods, that also includes insects, and myriapods (centipedes and millipedes).
I love skulls, this belongs to the sea robin, a fish that looks like it walks over the floor of the ocean. They are often caught by fishermen, either these fish get caught in the tide and are eaten by birds or they are caught by fishermen, used for bait and discarded.
A horseshoe crab does not have a poisonous stinger. The tail, or telson, as it is properly called is important to the crab especially in helping the crab right itself when flipped over. But, if trying to handle a horseshoe crab, grabbing it by the telson can cause it to break, which is no fun for the crab itself. 

Here is another stumper for me, personally... no. Not the brant, but the one making the fly-by. Unfortunately, it's blurry.
The Laughing Gulls are back for the summer!

One ruddy turnstone waits for the beach to clear, this bird also feeds on the horseshoe crab's eggs. 
A red-wing blackbird photobombs a perfect Manhattan skyline.
More fish skulls. This is the part where my husband yells at me for touching dead things.... 
Fairly sure this is a least sandpiper...

     After being sad about not seeing red-knots and the birds being chased away, my husband said we could go to Jamaica Bay Refuge. This made me feel better. Here is what we saw.... Warning: Extreme cuteness ahead...

You don't need to like geese, but if you don't find this cute, well, then, we shouldn't talk...
Me: "You hear that??"
My Husband: "No."
Me: "It is singing, 'drink your tea!'"
My Husband: "No. I don't hear something saying 'drink your tea...'"
An Eastern towee. Listen here
A blurry little blue heron, a first for me, and I suppose my husband too.
Those are Eastern tent caterpillars, which have constructed a silk nest in between the branches of this tree.
An Osprey sits on its nest. The osprey at Jamaica Bay has his own blog too.

They were paddling so hard against the outgoing tide. Tough little guys! And cute too!
My husband spotted this yellow warbler.
Song Sparrow.
The parents were being protective of their baby. Good job, mom and dad!
Baby learns the goose attitude from mom and dad. His little hiss though seems incredibly non-threatening....
A tree swallow claims a nest box.

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