From Snails to Whales: Assignment 3

Monday, August 3, 2009

Assignment 3

Hi everyone! I'd like to start out by revisiting some things from our previous blog and make some changes/additions to my post. First off, while i still think the changes between this years barking crab observations and last years are due to increased rainfall, decreased salinity, and increased nutrient concentrations, i think the main impact of these changes is seen in the amount of brown algae present. In the picture from last year, there isn't as much brown algae compared to this year's observations. This is because the increased nutrient concentration from all the rain we have had this year is mainly affecting the algae, a primary producer in the ecosystem. I think that a significant increase in the amount of algae is detrimental to the growth of the other species we saw, such as mussels and tunicates, which is why there also seems to be more variation of organisms and larger mussels in the picture from last year. One way to test this theory would be to conduct a mesocosm experiment in a lab, with multiple tanks that mimic the environment at the barking crab as closely as possible but with variations in salinity and nuteirnt concentrations. This way, we could directly observe the effect that changes in salinity and nutrient concentrations would have on all the organisms present and specifically the growth of brown algae.

As for the mystery cheeto-like creature that i had previously identified as the reb beard sponge... I now think this is an orange or red sheath tunicate. It is thought that they got here from hitchiking on the bottom of boats from the Pacific, which is why they were not found in our guide books. They are an invasive species which tend to out-compete native organisms of Boston Harbor in brackish water conditions, which is why we saw most of them at the barking crab where fresh storm water is drained into the bay (1,2).

Now to move on to some observations made at Lovells Island. First, the common periwinkle. It seems to an accepted idea that the periwinkle is not entirely native to New England, both in our guide book and on the internet. It was originally from Western Europe, was brought to Novia Scotia, and has now migrated south to New England over 100 years ago. However, there does seem to be a debate about whether or not this invasive species is having a profound effect on the landscape in inhabits. One side beileves this species is completely harmless, the other thinks it is transforming sandy beaches into rocky beaches. There seems to be a lack of scientific study from both perspectives, however, so it is difficult to come to a solid conclusion one way or the other. I personally am leaning towards the idea that the periwinkle is causing a transformation of the North Atlantic seashore simply because i find it hard to believe that an invasive species would not have an effect at all on an enviroment that it is not native to. This idea just does not follow the trend we have been seeing for several years regarding the impact on most invasive species in all types of environments (3). I also think that their main predator in New England is probably the Northern Moon Snail. I am basing this off of the holes we saw in the shells of dead periwinkles that appeared to have been made by some sort of tiny drill. The moon snail feeds mainly on periwinkles and clams in the intertidal zone by drilling through the shells of its prey with its radula and digesting/sucking out the soft parts in the middle. In addition, the moon snail tends to bury itself deep within the sand of the intertidal zone, which is why we did not actually see any of them among the rocks and periwinkles (4). Since we saw these holes in both clam shells and periwinkle shells, and since the habitats of the two overlap extensively, i am pretty confident that the moon snail is to blame for the holes that we saw.

At the tide pool, we saw a lot of rockweed, periwinkles, barnacles, and algae, but the most amusing creature was a type of small crab, pictured below.

I believe this crab species is an asian shore crab, and invasive species originally from the Korean and Chinese coasts, based on its coloring, body shape, and agressive behavior. Though they try to put up a tough fight, they are pretty small and their claws do little damage, making them cute and fun to play with! I thought finding these was the best part of the Lovells Island trip.

The land snails we saw, pictured at the right, are likely to be a combination of two different

species: the grove snail and the white-lipped snail. The snails with the lighter colored body are white-lipped, and the darker colored body ones are grove snails. Both species has a wide variety of shell colors, including those we observed on the island. They are indeed invasive, originally coming from Europe as the most common type of land snail there. They probably got there by hitchiking on shipments of plants or vegitables and have found the Sumac tree of New England to be a perfect habitat (5,6). My theory on how the snails ended up in a concenrtated area on the beach is tat Bruce put them there. However, if he had not, they could have easily been washed down to the beach from the Sumac trees and walls of the old forts inland on the island by rainfall, which on an island tends to drain to the ocean as it is in general the lowest level of elevation. The distribution of shell colors i think are due to the primary haibtat of a snail's gene pool. A snail that is found in dark colored tree bark will likely have more and thicker brown stripes on their shells to blend in with the brown color, snail found grazing in leafy greens will be some variation of yellow with thin brown stripes, and a snail found living within the walls of the forst will have a dull pinkish/brown color to blend in with the dirty walls and the surrounding soil of its habitat.

Overall, yesterday was incredibly fun and i had a great time!

See you all in class,
Sam Gifford

Sources:
1) http://www.armofthesea.info/flora_fauna/ff_speciespp/chordata.htm
2) http://stellwagen.noaa.gov/education/adulted/invertid_tunicates.html
3) http://www.cobscook.org/cobscookBay/soundings/art10-per.htm
4) http://en.wikipedia.org/wiki/Northern_moon_snail
5) http://en.wikipedia.org/wiki/Grove_snail
6) http://en.wikipedia.org/wiki/White-lipped_snail
7) http://fl.biology.usgs.gov/Nonindigenous_Species/Asian_shore_crab/asian_shore_crab.html

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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

Monday, August 3, 2009

Assignment 3

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