BOHA Waterbird Monitoring Update: June 28, 2011

Tuesday was exactly the kind of day for which we wish!  Sunny and calm, not too hot…. Perfect!

Least Tern chick on Lovells Island (CLT, 6.28.2011).

 

The Least Tern colony on Lovells Island continues to be very active with approximately 80-85 adults attending.  We began a second complete nest count, but quickly chose to abandon the effort since many young chicks were present and we did not wish to cause unnecessary disturbance during such a critical phase of the breeding season.  The Great Black-backed Gull earlier reported to be nesting on Lovells was carefully brooding two chicks just outside the tern colony.  This is the first record I know of a nesting gull on Lovells – as Marc said earlier, ‘Nice to live close to where you eat.’  We’ll see…

Great Black-backed Gull Brood on Lovells Island (CLT, 6.28.2011).

 

A boat-based survey of the Outer Islands turned up 159 Common Eider chicks associated with 86 females.  An additional 357 females were in the area.  Compared to previous years, these numbers suggest only moderate success this season.  We also kept watch for any dead adult eiders on island beaches, but saw done.  In addition to eider chicks, we also observed a pair of territorial American Oystercatchers on Outer Brewster, and another pair with one fledged chick on Middle Brewster!  We spotted at least 3 gray seals around The Graves, several Wilson’s Storm-petrel east of the Brewsters, Spotted Sandpipers on Middle and Outer Brewster, and one immature Great Cormorant on Shag Rocks.

Common Eider females tending chicks (CLT, Green Island, 6.28.2011).

 A boat-based survey of the west side of Great Brewster resulted in one pair of territorial American Oystercatchers.  No accompanying chicks were spotted, but the fact that the adults are still on territory is encouraging.  There were also approximately 47 additional female Common Eiders in the area. 

 We finished the day with a complete boat-based survey of Rainsford Island.  No American Oystercatchers were observed, but lots of Spotted Sandpiper activity was noted and 9 additional female Common Eiders were in the area.   Back out on July 6^th!  Happy Fourth of July!

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BOHA Waterbird Monitoring, 6/20/2011

Our last trip before the Summer Solstice occurred on Monday, June 20^th.  The weather was lovely with Our last trip before the Summer Solstice occurred on Monday, June 20^th.  The weather was lovely with very light winds, so we took advantage of the opportunity to conduct a boat-based survey for Common Eider chicks around the Outer Islands. We ended up with a total of 199 chicks on our regular Outer Islands circuit – and then saw five more feeding off the rocks on Lovells a bit later in the morning. 

Common Eider with chicks off Shag Rocks (CLT, 6.20.2011).

This was our first real eider crèche survey this year and numbers seem reasonable given previous years data.  For comparison, in 2010 we counted 341 chicks on 6/16 (!) and had counts of over 250 throughout the season, but in 2009 we reached our high count of 196 in early June and plummeted from there.  It will be interesting to see what we turn up next week.

 

Double-crested Cormorant nesting colony (Middle Brewster, CLT 6.20.2011).

We also observed an incubating American Oystercatcher on the landing beach on Outer Brewster and an active pair on the landing beach on Middle Brewster.  No other AMOY were observed, so the fate of those we saw on Calf, Little Calf, and Green are unknown.  Though we did not see any Great Cormorants, nesting Double-crested Cormorants remain very active feeding young.  We also observed a couple of Wilson’s Storm-petrels in the area, and at least 2 harbor seals and 4 gray seals around the Graves.   

Hauled out Harbor and Gray Seal (The Graves, CLT 6.20.2011).

 

The Least Tern colony on Lovells remains active.  We did not conduct a complete count, since we had been there only 5 days earlier, but we did check in on adult numbers and they seemed stable.

Least Tern nest on outskirts of Lovells Colony (CLT, 6.20.2011).

 

Thanks to Marc and crew for posting signage in the area. 

Lovells Island Least Tern Colony (CLT, 6.20.2011).

Killdeer chicks we had previously noted on the beach last week also seemed to be coming along fine (does anything look more ridiculous that a baby Killdeer?) 

Killdeer chick (Lovells Island, CLT 6.20.2011).

 

Susannah and Pat also observed a pair of territorial American Oystercatchers on the north side of Lovells.  Although we did not find chicks, their behavior strongly indicated they had unfledged young nearby – a first for Lovells!

 

Hard-working Volunteers!

Enjoy these long days – maybe we’ll even see the sun sometime?!?

-Carol

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BOHA Waterbird Monitoring, 6/16/2011

After another bout of awful weather, we were finally able to get back to the islands on Wednesday, June 16^th.  

Least Tern Colony, Lovells Island (CLT 6.16.2011)

Our reward was 75 Least Tern nests on Lovells!  (See above – not bad real estate, huh?)  There was also a pair of Killdeer with 4 chicks on the beach nearby.  

Nesting Least Terns and Killdeer (Lovells Island, CLT, 6.16.2011)

After leaving Lovells, we headed to the tern nesting platform off Spinnaker Island, near Hull.  At first it appeared there was little activity,

No Common Terns this year? (Spinnaker Tern Platform, CLT, 6.16.2011)

but once Russ brought the boat all the way in to the piling, VIOLA!  We estimated that (approximately) 133 adult Common Terns flushed from the platform.

Common Tern Nesting Platform (Spinnaker Island, CLT, 6.16.2011)

A cruise by the beaches surrounding Prince’s Head on Peddocks turned up no American Oystercatchers this year.  However, we did count 29 nesting or brooding Great Black-backed Gulls on Hangman, along with one nesting Double-crested Cormorant – a first for me!  There was also a pair of territorial American Oystercatchers spotted on Hangman, though no chicks were observed.  We attempted a trip to the Outer Islands, but were rebuffed by rough seas.

Hopefully, we’ll have better conditions for eider chick counting when we head out tomorrow!  Also of note, you may remember that we sighted a Herring Gull with a green wing tag on Great Brewster a couple of weeks ago – the following information about that bird was provided to me by Ken Mackenzie from DCR:

 Here is some specific information on K99:Captured 2/4/11 at South Bay Center, South Boston, MA; Capture location (GPS): 42.3297805, – 71.063811; Captured using a rocket net baited with crackers and bread; Adult male herring gull; Green wing-tags: K99; Red leg band: 55; Federal leg band: 1146-31807; Released on site:  Sightings:  This is the first sighting of this gull since its capture in February.  Thank you!

 Ken would love reports of other tagged gulls, so please keep your eyes open!

 

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BOHA Waterbird Monitoring Update, 6/4/2011

After a slow start to the season, we’ve had two weeks of glorious weather and finished up May with a lot to show for our efforts!

The Graves, 5.25.11 CLT.

We kicked off the season for real on Wednesday, May 25^th with a boat-based survey of the Outer Islands.  Have you ever visited the Graves on a day like this?!?  Incubating gull and cormorant numbers appear generally similar to previous years (see boat_counts_boha11.pdf, attached) – special thanks to Bob K. for observing and Pat for testing out electronic data collection with CyberTracker!  Upon reaching the Outer Islands, we were greeted by three pair of American Oystercatchers just south of Calf Island.  Based on observations during the rest of our loop, we believe that at least one pair is nesting on Calf and one pair on Middle Brewster.  The third pair may have come over from Great Brewster (see 5/26 report) or there may be a second pair on Calf.  We also spotted single adult AMOYs on intertidal rocks on Little Calf and Green Islands.  There were still lots of adult male and immature male Common Eider ‘hanging around’ and 42 eider chicks were observed in small groups around the Graves, Middle, and Outer Brewster.   (Although we missed our window to assess nesting eider this year, we will be tracking chick numbers beginning in mid-June.)  Other items of note were 2 Harbor Seals on the rocks near Green Island, a juvenile Great Cormorant also on Green, and an adult GRCO on intertidal rocks off Outer Brewster – a future nesting waterbird species perhaps?  On our way back to the dock on the 25^th, we checked out the beach on Lovells where a few Least Terns were circling, but no nesting activity was noted.  We also observed 2 AMOY feeding off Lovells and counted 14 nesting Herring Gulls and 15 nesting Great Black-backed Gulls on Gallops.

American Oystercatcher nest with two chicks on Great Brewster Island (5.26.11, CLT).

We headed back out on the 26^th, taking advantage of the high tide and starting our morning with a visit to Snake Island in Winthrop where we observed 5 pair of American Oystercatchers and 5 pair of territorial Willets.  In an effort to minimize disturbance, we did not search heavily for nests but territorial behavior was definitely apparent.  Two Least Terns and 2 Common Terns were spotted in the area, but there was no indication of nesting.  Also of note were Black-bellied Plover, White-winged Scoter, Killdeer, Ruddy Turnstones, Northern Rough-winged Swallows, and a Saltmarsh Sparrow (a species I had previously seen on Snake… though apparently Bob S. didn’t really believe me until he saw it for himself!)  A visit to Great Brewster yielded 2 additional AMOY pairs who both nested on the landing beach where one pair has been found in previous years.  The first nest held one egg and two brand new chicks being earnestly defended by their parents from interested gulls at the ready nearby.  (My advice to nesting oystercatchers is – DON’T BUILD YOUR NEST NEAR A GULL COLONY – they never seem to listen to me….) Combined gull counts on Great Brewster resulted in 108 Herring Gull nests and 9 Great Black-backed Gull nests, most of which held 3 eggs.  We also observed a Herring Gull with a green wing tag numbered 99, which appears to be a bird tagged as part of a DCR water supply study (see http://www.mass.gov/dcr/watersupply/watershed/study/index.htmfor more on this).  A loop around Spectacle on our way back in yielded a whole lot of nothing, but it does not look like mowing has taken place yet, so that is great news for nesting birds.

Carl & Susan nest searching on Great Brewster (5.26.11, CLT).

This past week we spent Tuesday, May 31^st conducting boat-based surveys in the Dorchester and Hingham areas.  It appears to be a busy year for American Oystercatchers with a single adult spotted on Slate, 1 pair on Bumpkin, 1 pair on Sarah, 1 pair (with 2 chicks!) on Button, and 2 pairs with a possible 3^rdon Sheep.  Gull and Cormorant numbers were similar to previous years:  Sarah (101 HERG, 11 GBBG, 85 DCCO), Ragged (1 HERG), Button (8 HERG, 2 GBBG), and Sheep (123 HERG, 4 GBBG, 15 DCCO).  Cormorant numbers on both Sarah and Sheep are up from previous years and Herring Gulls seem to be down, but I haven’t yet had the chance to run through all the numbers.  Also, although not our primary focus this year, wading bird colonies on Sarah and Sheep were quite active with all the expected species present.  Finally, a landing on Rainsford turned up 2 MORE pairs of AMOY, 2 nesting GBBG, 1 nesting HERG, and approximately 11 territorial Spotted Sandpipers – an extremely consistent figure, though we had little luck with nest searching in 2010. 

Sheep Island (5.31.11, CLT).

So for those of you keeping score at home, it appears we have at least 17 or 18 pairs of American Oystercatchers on territory in the islands, and we haven’t yet visited Thompson or Peddocks.  So, we are on track for consistently high numbers again in 2011!   We’ll be back out counting again the week of June 13th…  See you then!

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