Monitoring at MacMillan Wharf, Provincetown, MA

Monitoring at MacMillan Wharf, Provincetown, MA
Marine Invasive Species (MIS) Monitoring at MacMillan Wharf, Provincetown, MA.

Friday, November 11, 2011

Marine Invasives Monitoring

My monitoring activities at Provincetown, Wellfleet, Salem, and Beverly Marinas are now completed for 2011 with the Species Reports for Ptown and Wellfleet sent off to the CZM and my marine biologic image collection significantly enlarged.  With 4 months of visits behind me, I obtained a nice selection of photographs of Massachusetts marinas and their marine invasive species (MIS).  After several of the trips, I was able to get brightfield microscopic images of colonial species within a few hours of their collection.  Fourteen of the sixteen species on the list in the August 8th Post were seen this season, all except the European oyster Ostrae edulis and leafy red alga Grateloupia turuturu.  Among the sessile or attached species, Didemnum vexillumStyela clavaBotrylloides violaceusBotryllus schlosseriDiplosoma listerianum, Ascidiella aspersaBugula neritinaMembranipora membranacea, and Codium fragile were commonly observed, whereas Diadumene lineata found a special niche in the Wellfleet Marina. 
The most dramatic event of the summer was the impact of Tropical Storm Irene which had a major erosive impact and removed most of the species that were not strongly attached or that extended out from the docks.  My visits to Cape Cod occurred 2-3 days after the storm, and the storm currents cleared away much of the overgrowth and removed some of the species down to the substrate. 
Perhaps the most impressive and beautiful species to my eye was Botrylloides violaceus, whose bright orange colors could be seen by casual observation walking on the docks and which looked even more beautiful up close when the meandering rows of zooids and their surrounding ampullae could be clearly observed.

Botrylloides violaceus in Clear View at Low Tide on a Pier Piling
 at Fisherman's Wharf, Provincetown, MA
The green alga Ulva lactuca grows above a band of orange Botrylloides violaceus. A colony of Didemnum vexillum can barely be seen below the Botrylloides.

Botrylloides violaceus Orange Colonies on the Sides of Dock Floats
View of the side of a dock at MacMillan Wharf, Provincetown, MA. Looking through the hazy water, light-orange, orange, brick-red-orange, and purple-red-orange color variants of Botrylloides can be distinguished. Also present were mature Mytilus edulis and Styela clava.

Botrylloides violaceus Colonial Organization 
Botrylloides colony showing meandering rows of zooids with open branchial siphons separated by clear tunic containing a border of amplullae.  3X zoom x 10X objective.

Botrylloides violaceus Zooids and Ampullae 
Orange color variant of Botrylloides showing branchial siphons, pigmented body wall, and pigmented ampullae between rows of zooids. Endostyle is in subtle contrast to body wall.
3X zoom x 10X objective.

Botrylloides violaceus Endostyle and Branchial Features
Light-orange color variant showing branchial tentacles and orange-pigmented endostyle against the more transparent body wall.  3X zoom x 10X objective.
Additional stereozoom micrographs of Botrylloides violaceus and other ascidians can be seen at