Week 5: Arthropods and Invertebrates

Date: May 5, 2013
Weather: sunny, light wind
Temp: 72 F
Time: 1:00pm-3:00pm
Location: Discovery Park

Starting with a picture of the west side of
Discovery Park to celebrate the nice day

Ahhhhh! The first great (field) day of Spring! Not a cloud in the sky! The mission for this bright and sunny day: find Arthropods! Arthropods are invertebrate animals having an exoskeleton, a segmented body, and jointed appendages. They are members of the phylum Arthropoda, and include the insects, arachnids, and crustaceans. Unfortunately, the only source of moisture at Discovery Park lies along west edge at the beaches...no streams or lakes to go poking around in, so we were unsure of our prospects with the invertebrates. At first, we explored the western central side of the park, but then determined it might be too windy, especially for insects (the class of winged Arthropods), so we went into more wooded areas. We spent almost two hours searching before we had even considered going down to the beach to look at Crustaceans, and so we hope to get down to the beach next week.
However, we were able to see many busy bees (Order Hymenoptera) pollinating a lavender plant:

A beautiful, golden Honey Bee

Another type of Honey Bee?

The back view of a Yellow-Faced Bumble Bee

And nearby, a Western Yellow Jacket hides in the grass, skulking at these busy bees...

Western Yellow Jacket--tread lightly!

Western Yellow Jackets are actually a type of wasp. They do have workers that forage for food, but many devote their energy to aggressively defending the nest. This is because they will forage almost anything, from leftover picnics to flowers, a la raccoon-style. Adults feed primarily on items rich in sugars and carbohydrates, such as fruits, flower nectar, and tree sap, while larvae feed on proteins, such as insects, meats, and fish. Adult workers chew and condition the meat fed to the larvae. Larvae in return secrete a sugar material relished by the adults; this exchange is a form of trophallaxis (mouth-to-mouth or anus-to-mouth feeding). In late summer, foraging workers change their food preference from meats to ripe, decaying fruits, or scavenge human garbage, once larvae in the nest fail to meet requirements as a source of sugar.
Looking down at my jeans, we notice a fly (Order Diptera) just hanging out.

House Fly?

We classified it as a House Fly, based on the red eyes, but are not completely sure. We also saw a group of flies hanging out on some flowering Lupines

House Fly(?) on Lupine

We were not quite sure why these flies wanted to hang out on unopened flowers unless they were not there to feed. A look at my Audubon field guide shows that apparently flies have an even less glamorous lifestyle than the wasp. The guide describes their lifestyle habits as "sucks liquid sugars from garbage; spreads disease." Alright, I guess I can see why the expression "Shoo, fly, shoo!" exists...
Moving on, we saw a spider (Order Araneae) scuttling across the path, which we were unable to identify

My spidey sense is tingling

Nearby, there was an group of ants (Order Hymenoptera, same as bees) crawling all over the flowering American Vetch

Unknown ant species

They appeared to be crawling all over the vetch aimlessly, except when they would pause beneath the flowers, possibly foraging for dripping nectar or other plant matter.
This was the extent of our Arthropod-finds for the day, though we noticed some new plants, and several familiar species beginning to fruit or flower:

Fruiting:

Elderberry

Red-Flowering Currant

Indian Plum

 Flowering:

Lupine

Also Lupine, but completely different flower structure,
so we're guessing it's a second species!

New species in our area:

Willow with spiky catkins

Columbine

Columbines elongated petals that curl at the back reveal it
as an evolutionarily specified hummingbird pollinated species

Pacific Bleeding Heart

Deer Fern

Cedar of Lebanon

Vine Maple

Some kind of Lily--distinguishable
by parts being in multiples of 3

Flowering Rosaceae plant

??

?? Tips of the Douglas Fir, some Pineaceae species perhaps

Here's hoping for beautiful weather next week!
I leave you with my picture of the week. This was not at Discovery Park, but was from some sort of Pine species outside the University of Washington campus.

Welcome, Spring!