This view is like a dream sometimes.
Also spotted in Brooklyn Bridge Park:
Posts Tagged 'invertebrates'
Below the bridge
Published May 21, 2012 Fieldnotes 2 CommentsTags: birds, Brooklyn Bridge Park, insects, invertebrates
Galls and Crane Fly
Published May 20, 2012 Fieldnotes Leave a CommentTags: insects, invertebrates, trees
A two-fer in this shot of a Witch Hazel leaf:
This is a boom year for the Witch Hazel Cone Gall-maker (Hormaphis hamamelidis), an aphid. Read more about these tiny insects and how they force the American Witch-Hazel (Hamamelis virginiana) to create these protective cone forms around their young. For more about the endlessly fascinating galls read here.
The insect perched here looks like a Genus Trichocera Winter Crane Fly. There are some 28 species in this genus in the the U.S. and Canada, and as their name suggests they can be found in the winter months, particularly in caves and mines.
If you read this, you are probably also reading Marielle Anzelone’s Spring series at the New York Times. If not you should be. Yesterday’s article introduced us to the Viburnum Leaf Beetle (Pyrrhalta viburni) an invading species which devours Viburnum species, especially Arrowwood (Viburnum dentatum).
Well, yesterday afternoon in Van Cortlandt Park, I met one of these beetles in person, at least in its tiny larval stage. This is just one of the instars, or stages of the beetles’ larval growth:
Small, but hungry.
American Copper
Published May 10, 2012 Fieldnotes Leave a CommentTags: butterflies, insects, invertebrates, Nantucket
Lycaena phlaeas. Common name aside, the East Coast population of this small butterfly is thought to have been introduced from Europe during the colonial period, probably on the sheep sorrel its larva feeds on. It is notably associated with these invasive sorrels, and often found on disturbed habitats like roads and lawns, where I’ve photographed them. The Western population is found at and above the timberline and reaches up into Alaska and arctic Canada.
The Hunt for Red Admiral
Published May 8, 2012 Fieldnotes 6 CommentsTags: butterflies, insects, invertebrates, Nantucket
Red Admiral butterflies (Vanessa atalanta) are out in force this year, enough to be noticed by my radio station, WNYC. This is probably an East Coast phenomenon, as I was on Nantucket this weekend and saw many but photographed few. Being so fast, flighty, and flittery, butterflies are generally hard to photograph. Red Admirals are especially erratic and fast in flight, and when perched they see you coming way before you see them. I managed these shots because this particular one kept returning to the window and the surrounding shingles so I could just stand there and wait.
I suspect therefore that it is one of the males, which the Kaufman Field Guide says are “especially pugnacious” in defending their territory; this one actually chased after a bumblebee! I suppose that he was trying to chase away me, too, so I left him to the sun. According to the Kaufman, this species sometimes migrate north in large numbers.
When these perch with their wings closed, they are much harder to notice, especially on a woodland path:
Vanessa atalanta is an especially beautiful scientific name: Vanessa is from the Greek for butterfly; the Vanessa genus also includes the Painted and American Ladies; Atalanta was the mythological Greek hottie who was swift of foot but had an eye for the golden apples. Wikipedia tells me that V. atalanta is mentioned in Pale Fire, which I just started to re-read this weekend, coincidentally.
Lady Bug
Published April 27, 2012 Fieldnotes 2 CommentsTags: beetles, Brooklyn, insects, invertebrates
My first lady bug of the year. The Multicolored Asian Lady Beetle (Harmonia axyridis) is also multi-spotted, or sometimes not spotted at all. It’s highly variable, with more than 100 (!) colorforms. The M-shape on the pronotum is usually a good marker of the species. Of course, that’s a W-shape if you look at it the other way. (That seems to make it the only beetle with my initials on it.) The species was introduced into the Southeast around thirty years ago; since then it has spread throughout much of North America.
Polygonia demystified
Published April 21, 2012 Fieldnotes 2 CommentsTags: butterflies, insects, invertebrates
Eastern Comma butterfly (Polygonia comma). I found this photo in my archives and thought I would compare it to this photo of a Question Mark butterfly (P. interrogationis) I took the other day:
These butterflies’ common names come from the small silver marks on the underside of their hindwings (the lower of the pair), which look like our common punctuation marks. These marks are quite hard to see in the field, but of course taxonomists tend to work with a dead specimen and see things hard if not impossible to see in the field.
There are a number of differences between these two species, but the telling field sign is that the Question Mark has an extra spot on its forewings. Note where both butterflies have a row of three spots through the center of their forewings. The Question Mark has another spot, rather more rectangular than its siblings, between the broad marks that come in from the front edge of the forewings.
Friends! Are you troubled by little gray-black flies that, upon closer inspection (don’t be shy, get a little closer, the details are remarkable) look rather moth-like with their hairy wings and bodies? Do you wonder why they seem to be hanging around your sinks? Or, like this one, in the hallway, just waiting for my defenses to be breached?
Well, trouble no more, you’ve discovered the subfamily Psychodinae, the moth flies. Yes, it’s a confusing name, sort of like “spider beetles”. These are also known as drain flies since they breed in the rich bacterial slime that collects in home drains. (Ahem, present company excepted, of course.)
These are just under 1/4th inch long.
A Very Strange Crab Indeed
Published March 26, 2012 Fieldnotes 1 CommentTags: Brooklyn, Dead Horse Bay, invertebrates, Jamaica Bay, St. John
A piece of barnacle conglomeration I found at Dead Horse Bay recently. Most species of barnacles need a surface to attach to, and sometimes that surface is other barnacles. These are a type of acorn barnacle, one of the two main groups. I understand differentiating the local species is difficult for the lay person. Give a shout if you know them on sight. Commonly seen species in the region are the Ivory barnacle, Balanus eburneus, which prefers less saline water (like Jamaica Bay, so this may be that) and the Northern rock barnacle, B. balanoides, which likes it saltier. 
A barnacle, as Cirripedia-mad Charles Darwin discovered, is actually a crustacean, akin to crabs and lobsters. A free-swimming animal in its youth, it has two distinctive larval stages, wonderfully called nauplius and cyprid. Then after swimming through several instars, most barnacle species settle down, literally, gluing themselves head/forehead first to a rock, pier, ship’s hull, or some such surface, and enveloping themselves within a carapace-like shell made up of (usually) six plates for an immobile maturity. The references to ship’s hull is a matter of some economic seriousness; humans have been scraping barnacles off boats since we took to the sea. The beak-like barn doors that protect the soft animal within its calcium fortress are visible in the above image; when feeding, these open to allow feathery modified legs that pull in plankton from the water. Barnacles at the mercy of the tide hunker down during the hours of low tide.
There are many species of barnacles; I came across numbers ranging from 900-1100+. Pictured above are the ruins of Ribbed barnacles, Tetraclita stalactifera, which I found amid the rocks of Klein Bay, St John, USVI in January.
Arthropods of St. John Part II
Published January 28, 2012 Fieldnotes 3 CommentsTags: invertebrates, St. John
One of the ubiquitous arboreal termite colonies, or termitaria, found on the island. Known locally as wood lice or wood ants, this Nasutitermes species builds large nests of partially digested wood pulp mixed with their own saliva and feces. The material looks like mud from a distance. The nests are often found broken up on the ground, brought down by their own weight. Here’s a chunk of the brittle, friable nest: 
These critters do not like the light: they even turn their trails into tunnels, as this one, snaking up a tree:
I found this tunnel across a path. It had been stepped on by an earlier walker:
If you look closely, you can see two of the three termite castes in this scrum: the round-headed workers and the pointy-headed soldiers (their heads are also darker). The soldier’s proboscis sprays noxious chemicals in defense of the colony. I didn’t smell anything unusual, probably because the disruption was already over and now the termites were working to repair the damage. The third caste, the reproductives, are generally only seen in the fall when they take to wing.
Termites from a single nest may build tunnels in a territory as large as a football field. They generally don’t eat living wood, so they are recyclers of dead wood in the forest. Their waste pumps nitrogen back into the soil. Wood pulp is really hard to digest, so the termites’ guts are loaded with cellulose-digesting bacteria. It’s a symbiotic relationship — like that of humans and our intestinal flora, which consists of something around 500 species! — one passed on, literally, via the young eating the liquid intestinal stew secreted from the business ends of older termites. “Proctodeal feeding,” to the pros. Now, carry on with your breakfast, and feed that gut flora!
