Thursday, July 15, 2010

Harbour Porpoise Release Program 2010

Our Harbour Porpoise Release Program has been a formal program since 1991. Each year a number of harbour porpoises are trapped in the passive fish traps called herring weirs which are heart shaped traps with a long fence leading to shore made of wooden stakes wrapped with netting. A few floating weirs are also used which are made from PVC pipe in a ring with netting suspended below.

This year has not been an exception with at least three harbour porpoises entrapped. Fortunately two porpoises swam out themselves with the third just reported from the same trap. Small minke whale entrapped in a herring weir. The whale swam out that night without assistance.

There have also been two minke whales entrapped in two different herring weirs, one that has also had the three porpoises and another weir on the western side of Grand Manan. Both minke whales swam out themselves.

Because our researchers are not arriving until the beginning of August, one of the nets specially designed for the safe removal of porpoises from weirs has been made available in the harbour in North Head. The weir operators have free use of the seine.

Thursday, May 20, 2010

Great Shearwaters Start to Move

The satellite tagged greater shearwaters in the South Atlantic are starting to begin their migration to the North Atlantic after spending time off Argentina preparing themselves for the long trip. Several birds are now off Brazil. http://www.seaturtle.org/tracking/index.shtml?project_id=452

The northward migration of the greater shearwaters have never been tracked by satellite and it will be interesting to see the route, just as it was the first season our researcher, Rob Ronconi, placed the first satellite transmitters on shearwaters in 2006. Tracks for the three years of tracking greater shearwaters in the Bay of Fundy and their southward migration can be found at:

2006: http://www.seaturtle.org/tracking/index.shtml?project_id=176
2008: http://www.seaturtle.org/tracking/?project_id=311
2009: http://www.seaturtle.org/tracking/index.shtml?project_id=436

In 2007, two sooty shearwaters were tracked: http://www.seaturtle.org/tracking/index.shtml?project_id=237

Wednesday, May 5, 2010

Strangely Located Callosities

Right whale #3760 with back and side callosities
in addition to the callosities on the head

Right whales are known for their callosities on their face where facial hair is often found, eyebrows, mustache and chin whiskers and these are used to identify individuals. However, a right whale calf was born in 2007 with additional callosities on its back and right side, #3760, the calf of Derecha, #2360. First seen on June 2, 2007 as a tiny calf in the Great South Channel off Cape Cod, this calf hadn't been seen in the calving area off Florida and Georgia in the winter and is thought to have been a late birth.
Derecha is an unusual mother and seems to want to head south when she has a calf. In 2004 after being seen off Florida she was spotted off Texas in the Gulf of Mexico! She eventually turned around and was spotted in the Bay of Fundy in September. In 2007 after being spotted off Cape Cod with her tiny calf, the next sighting was in Florida on July 17! She turned up in the Bay of Fundy, again in September with her unusual calf. #3760 spent time in the Bay of Fundy last September (2009) when the photographs above were taken.

Monday, May 3, 2010

Antarctic Bound

One of our senior scientists, Dr. Andrew Westgate, is heading to the Antarctic as part of a team of scientists from the Duke Marine Lab. The expedition will take six weeks and a blog will be updated regularly.

Here is Andrew's email:

Hello family and friends!

Here is a link to a website that Duke has set up to document our upcoming Antarctic field trip. Postings are still up from the 2009 field season, but you can expect new updates soon. You can also see where the ship is on the map.

http://www.nicholas.duke.edu/nick-pro/antarctica/

Andrew

The southern hemisphere has been a popular spot for our researchers in the last year. Dr. Rob Ronconi, another of our senior scientists, spent three and a half months in the South Atlantic on Gough and Inaccessible Islands from September to December 2009 where he helped attach 22 satellite tags to greater shearwaters, among other research. Seventeen tags are still operational and we are waiting to see when the birds start their northward migration.

Rob is currently an observer on a research cruise on the vessel, CCGS Hudson, http://www.bio.gc.ca/vessels-navires/ccgs-hudson-eng.htm, on the Laurentian Fan off Nova Scotia and spotted a raft of sooty shearwaters that have already made it back to the North Atlantic from their southern breeding islands in the South Atlantic.

The movements of the greater shearwaters can be followed on the Sea Turtle website: http://www.seaturtle.org/tracking/index.shtml?project_id=452.

Thursday, March 25, 2010

Herring Gull Makes Round Trip

Who would have thought that herring gulls would be a harbinger of spring!?

One of the herring gulls tagged last spring on Kent Island, a small island off the coast of Grand Manan Island has completed a round trip from Kent Island to the Chesapeake Bay area and back. The bird was one of three that were fitted with satellite transmitters to follow their movements in the Bay of Fundy. The added benefit is that all three birds were migratory, spending the winter in Chesapeake Bay area. Normally this would be a great place for a herring gull but the area was plagues with severe winter storms this year. The other two birds have not returned yet and we wait to see if they will show site fidelity and nest again on Kent Island. the tracks of all three birds can be found at http://www.seaturtle.org/tracking/index.shtml?project_id=428.

Of the nine greater shearwaters fitted with satellite tags last summer, only two remain transmitting, over 200 days of data. The failure of the tag is often the battery but sometimes the birds die. One tag transmitter for several weeks from Inaccessible Island in the South Atlantic where shearwaters nest. it is suspected that the bird was prey to a skua, a large predatory seabird, which patrol the nesting colonies. We also had a transmitter returned last year from a Brazilian fisherman who had caught the shearwater on longlines. Bycatch in fisheries can be a major factor in seabird mortality. The birds are attracted to the baited hooks and can not see the hook. Surface drift nets may also entangle large numbers of seabirds. There are efforts in some areas to reduce the bycatch but it is still a problem in some areas. The tracks of the greater shearwaters can be seen at http://www/seaturtle.org/tracking/?project_id=435

Rob Ronconi, one of our seabird biologists, spent three months in the South Atlantic last fall including time on both Gough and Inaccessible Islands. He helped tag 22 nesting or pre-nesting greater shearwaters. The birds have been wide ranging from South America to South Africa in the same areas that the birds we have tagged from the summer in the Bay of Fundy also range once they reach the South Atlantic. Although four tags have failed, it is hoped that the tags last long enough that the northward migration may be captured as well as the forging in the South Atlantic. These tracks can be viewed at http://www.seaturtle.org/tracking/index.shtml?project_id=452