Day three – exploring the life along the docks.
Today was a scorcher!
Hot, hot, hot! Clear skies, no
wind to speak of and high humidity. We
started out observing and discussing tidal
zones between Commercial Peer and Long
Wharf . The tidal zones (supratidal, intertidal, subtidal zones) were explained as follows:
“The supratidal zone is the area above the high tide water line. The intertidal
zone is the area that is exposed to the air (twice daily) at low tide and
submerged at high tide. The subtidal zone is the area below the low tide water
line. This area is always covered by water”1
The tide was low and coming in and the water was clear to a
depth of approximately 3 to 4 feet. Gobs
of what appeared to be Rockweed was plentiful and green algae. We moved along Long wharf observing the
organisms living on the rocks and dock. The organisms living along the dock
were varied and plentiful as they are always in the water and are exposed to
the sun for most of the day. Here we observed barnacles on the dock pilings,
which I believe were native barnacles because tops of the plates were smooth
(not scalloped). We also observed
mussels, some type of sea lettuce, various organisms that appeared to some type
of kelp and/or seaweed along with an orange organism that appeared to be spongy
in nature. We continued our walk down to
Rowes Wharf where we observed the life growing
under the docks. The growing here were
again, muscles, some brown/maroon sea lettuce, common star fish, muscles,
barnacles and more orange stuff that I believed and still believe was orange
sponge was later (told) identified as orange truncate, but without the benefit
of a microscope, the identity of the orange organism was in question. However, after considerable research, I
believe the growth to be: Compound
tunicate, colonial tunicate; bright orange to red or purple in color; reaches
up to 10 cm; gelatinous colonies form dense clusters. Pathway: introduced from Asia; from the
Pacific in the 1970s, found in waters from Maine to Virginia; reported in LIS
(1980's), Impact: fouling organism - attaches to boat hulls, piers, lines,
traps, buoys, seaweeds. 2
We continued out walk to the docks at the Barking crab where
we observed the same organisms previously spied, but here we were able to pull
or cut off samples for closer observation.
At the Barking Crab we pulled what I believed to be golden star
tunicate, red alga, sea lettuce, kelp, and sea grapes . We also observed what appeared to be feather
duster, and insects identified as amphipods, barnacles, lichen, but accurately identifying the various
organisms by looking at a picture in a book is nearly impossible, so I’m still unsure
of what I observed.
No comments:
Post a Comment