From Snails to Whales: Day 4: Lovell's Island

Tuesday, August 3, 2010

Day 4: Lovell's Island

Hi everyone—

Today was a busy day! We took a ferry to George’s Island, and from there we took a small boat to Lovell’s Island. The island had lot of vegetation on it inland from the beach, including blackberry bushes (much to the group’s delight). The beach that we were on was sandy and then rocky closer to the water. It was also very low tide (that came up rapidly while we were there). Once we were on the beach, we waded through a few different tidepools of varying size, looking for life. The habitat was different from the one by the Barking Crab in a few ways. We were farther out to sea, and the life in the tidepools lives on the bottom of the ocean, as opposed to the creatures at the Barking Crab, which lived attached to various structures. Some things we saw were similar to the Barking Crab. We found mussels and crabs like we did at the Barking Crab, but we also saw some new things, such as lobster and periwinkles. The main difference between the two sites was, I believe, that these creatures live on the ocean floor, while creatures at the Barking Crab can live by hanging off the docks. Of course, some can do both, and that was why they existed in both habitats. The creatures we found include:

A periwinkle that I believe was the Common periwinkle (Littorina littorea), It is by far the most abundant snail in New England has is found on rocky shores between high and low tide lines. Periwinkles are an invasive species introduced from Europe 400 years ago, and they are changing the composition of the shoreline from sandy to rocky.

My partner and I also found some orange sheathe tunicate (Botrylloides spp.) This differs from the golden star tunicate we found at the barking crab because it looks more like one uniform structure in texture and color, rather than the separate shapes that form the golden star tunicate. The orange sheathe tunicate has rubbery crust and is found near the low tide line and below I shallow water, and it is found on the atlantic coast, among other places.

We also found many hermit crabs, which I believe were Long-clawed hermit crabs (Pagurus longicarpus), the most common hermit crab in Atlantic waters. It usually uses periwinkle shells as its home.

We found two asian shore crabs (Hemigrapsus sanguineus), which we identified as males because they had “rockets” on their undersides. I described these in my previous post, because we also found one at the Barking Crab. The two we found today were much larger than the one we found on Saturday. They were about 2.5 inches across. The most distinctive feature of this crab is that it only has three “teeth.” Asian shore crabs, like the common periwinkle, are invasive species.

We also found the common Atlantic slipper shell (Crepidula fornicata). The shell is humped with a shelf on the

inside. They are fixed to rocks. They are usually 1. 5 inches long and yellowish in color. (Source: http://www.britannica.com/EBchecked/topic/548836/slipper-shell.)

One other interesting thing that we noticed was that there were many shells with what looked like drill holes in them. I believe that this could have been caused by a number of different marine creatures. I found online that there are many types of mollusks that prey on other species by means of drilling through their shells. They use special mouthparts and enzymes to make the hole so that they can eat the soft parts of the snail or other mollusk. I also read that octopi can do the same. I found this on the website for the San Diego Natural History Museum: http://www.sdnhm.org/research/marine-inverts/marifaq.html I also read on line about boring sponges that create round holes in mollusks, I believe to live in them, here: http://www.seashell-collector.com/beginners/faq-f46/page_926.html. Finally, moon snails regularly feed on mollusks by using their radula to make a hole in the shell and feed on the soft parts of the mollusks. I found this information here, also at the San Diego Natural History Museum website: http://www.sdnhm.org/exhibits/mystery/fg_moonsnail.html.

Finally, in addition to the periwinkles in the water, we also found some snails on land, a grove snail. It was lighter because its shell was thinner, and their shells were more colorful. As opposed to the periwinkle, the grove snail had what looked like 4 antennae when it came out of its shell as opposed to the two on the periwinkle. There are two different kinds of grove snails, the white lipped snail Cepaea hortensis, and the brown lipped snail, Cepaea nemoralis. Usually they can be told by if their lip around the shell aperture is brown or white, but sometimes this is not the case. Otherwise, they can only be distinguished by dissection. I am not sure which type of grove snail the ones we found were, but in the picture it looks like both— one seems to have a brown lip and one has white. The two types of snails are found in similar habitats so this is far from impossible.

On the beach, we found five grove-snail shells all clustered by one rock on the beach. I believe this is because a bird uses that rock to drop the shells on, crack them open, and eat the insides.

Grove snails and the common periwinkle that we found in the tidepool look similar. In terms of classification, they are in the same kingdom (animalia), phylum (mollusca), and class (gastopoda). However, they differ when it comes to the next level of classification.

Source: http://www.arkive.org/white-lipped-banded-snail/cepaea-hortensis/description.html

I really enjoyed our day at Lovell’s Island. I feel as if I am starting to see the bigger picture of marine life in Boston Harbor: how organisms interact with each other, how they are related, and how they can affect the surrounding environment. I look forward to our next class!

- Sabrina Liu

No comments:

From Snails to Whales

Welcome to Snails to Whales, Bruce Berman's blog focused on both the little and the big things that make Boston Harbor such an interesting and extraordinary place to live, work and play.

With 50 miles of protected water, four sheltered bays, seven river systems, 34 islands and a nine-foot average tide, Boston Harbor is one of the most diverse urban ecosystems in America.

This blog focuses on the flora and fauna of Boston Harbor and Massachusetts Bay - on the beach, the shore, and the harbor islands, and in the cleaner waters of Boston Harbor and Mass Bay - including this ecosystems most important species - people.

During the summer, it is also a place for my Boston University Students and my colleagues at Save the Harbor / Save the Bay to share their work and experiences.

Where I am coming from...

Love that clean(er) water
Learning about the Boston Harbor Cleanup from the waterway’s eyes, ears, and mouthpiece

By Brian Fitzgerald, BU Bridge

On Georges Island, Bruce Berman talks with his students about the history of the Boston Harbor Cleanup,
which is largely complete. Photo by Vernon Doucette

Bruce Berman, aboard a ferry from Boston’s Long Wharf to Georges Island, poses a question to his students: “How clean is clean enough?”

He’s talking about the water below.

It’s a brilliant July day, with the smell of salt spray in the air. The sky is clear, and so is the ocean. But there was a time when Boston Harbor wasn’t so clean, when the stench of sewage assaulted the nostrils of anyone who went near it.

Berman is the communications director for Save the Harbor/Save the Bay, a public-interest environmental advocacy organization whose mission is to help restore and protect the harbor and Massachusetts Bay. He also teaches a Metropolitan College summer course called Politics, Public Relations, and Public Policy: The Boston Harbor Cleanup.

“The Boston Harbor Cleanup is an amazing success story, and I just love to share it with students,” says Berman, noting that the harbor’s “bad old days” weren’t that long ago. Those were the days when untreated human waste, syringes, condoms, and tampon applicators routinely washed ashore. The antiquated sewage treatment plants on Deer Island and Nut Island were so poorly designed and maintained that they flooded during even mild rainstorms, sending millions of gallons of untreated waste directly into the harbor.

Since then, bacteria counts in the water have decreased by more than two-thirds. Now the harbor teems with plants and animals, and people can legally dig for clams on Carson Beach in South Boston, which was unheard of in the 1980s.

“It was one of the filthiest harbors in America, and now it’s one of the cleanest,” says Berman. “What I’m trying to impress upon students is how this incredible comeback occurred, and how business, advocacy groups, environmentalists, and government can affect the outcome of large projects such as the Boston Harbor Cleanup through negotiation.”

Paradise regained

Berman points to the left as the boat cruises by the cleanup’s centerpiece: the gargantuan white egglike tanks of the Deer Island waste treatment plant, which in 1995 replaced the antiquated facility. The plant treats an average of 350 million gallons of sewage a day.

“And what comes out of the Deer Island treatment plant?” he asks. Berman, his booming baritone competing with the roar of planes taking off from Logan Airport, has a habit of putting students on the spot to see if they’re paying attention.

“The outfall pipe,” say several simultaneously. “Treated water,” chime in a few more.

“That’s right,” he says with a smile. “The plant separates the solid and liquid waste, and it pumps the treated water through the 9.5-mile outfall pipe, which empties into Massachusetts Bay. The resulting sludge is converted to high-grade fertilizer.”

Now Berman returns to his original question: “How clean is clean enough?” There’s no quick and clear answer to this one. “It’s a question that at the end of the day the federal courts had to decide.”

In 1985, a landmark federal court case required that the harbor’s beaches be made swimmable and fishable by 2000. Save the Harbor/Save the Bay was formed the next year to raise public awareness of the $4.5 billion Boston Harbor Cleanup. Sewer ratepayers in the 43 cities and towns financing the project cried foul over the prospect of astronomically rising bills, but because of the determination of environmental advocacy groups such as Berman’s, the cleanup was largely completed on schedule.

Berman says it isn’t finished, however. There are still frequent beach closures because the counts of Enterococcus bacteria exceed the federal and state standard for swimming. The culprit: filthy storm water and sewage, much of it from leaky pipes and illegal hookups emptying into storm sewers, and then into the harbor.

“So is the harbor clean enough,” the Springfield native asks his students, “when you can’t swim in it one out of five days in the summer?”

Work to be done

Berman and his class look out from Georges Island to Gallops Island (left) and the white tanks of the waste treatment plant on Deer Island (right). Photo by Vernon Doucette

This summer the state approved one of the last parts of the cleanup: the construction, by 2011, of a 2.1-mile tunnel near the Dorchester and South Boston shorelines that will hold sewage and storm water during bad weather. It then will be pumped to Deer Island for treatment.

Berman is ecstatic over this development, the result of “tireless negotiation and consensus-building,” he says. “After 2011, we’re looking at beach closings once every five years, when there is a major storm, instead of once every five days.”

But he is not about to let his guard down. To say that he is a man obsessed with the harbor cleanup would be an understatement. Berman is also Save the Harbor/Save the Bay’s “Baywatcher,” and he lives on his 40-foot trawler Verandah. Polluters beware: if you’re discharging oil or sewage into Boston Harbor, the Baywatcher just might be watching.

He is quick to point out that his zealotry is not just on behalf of the harbor’s flora and fauna. “The harbor is for everyone,” he says. “If you’re from a working class or poor family in Boston, and you can’t afford a Cape Cod getaway in the summer, a clean harbor is important. The same is true if you’re a tourist vacationing in Boston or you happen to live in a pricey waterfront condo.”

Accordingly, Berman, who was a political consultant and contributing editor to the Phoenix newspaper before joining Save the Harbor/Save the Bay nearly 10 years ago, also teaches his students about the harbor’s role in the city’s economy. He points out that in the early 1990s, just a few ferries cruised the harbor’s waters. Today, more than 100,000 people visit its islands each summer, discovering their ecological and historic treasures.

“The best way to protect the harbor cleanup,” Berman tells his students, “is to make sure that the public has access to the resources and can see a return on its investment.”

Trevor Kosmolsick (MET’05) has lived in Boston for seven years, but until taking Berman’s course, he had never been to the waterfront. “I’ve also wanted to go camping in the area, but I never knew that you could camp on a few of the islands,” he says. “Bruce Berman is not only a great professor, but the ultimate tour guide.”

He also backs up his words with actions. Sometimes he takes off his shirt and dives in the water to demonstrate to passing boaters that it’s safe to swim. To show people on ferries that fishing is safe, he’s been known to grab one of the bluefish or striped bass he’s caught and (very carefully) plant a wet kiss on it.

“What I want everyone to understand is that investment in the environment really does pay off,” says Berman. “We’re willing to pay for a clean Boston Harbor, so we should enjoy it.”

From Snails to Whales

Tuesday, August 3, 2010

Day 4: Lovell's Island

No comments:

Nature Blog Network

My Favorite Nature Blogs