sign in sign up
<<
Home , Mystic River, Wasque

Massachusetts Tern Inventory 2000

Bradford G. Blodget, State Ornithologist

Overview

The year 2000 was a challenging one for terns in . Long-term fundamental problems confronting terns asserted themselves during the 2000 season. The diabolical problems of predation and lack of suitable colony site alternatives work in concert to limit tern numbers and to threaten recovery and long-term stability of tern populations in Massachusetts.

For the second year in a row, fox activity precluded nesting at Plymouth . Although some 1,000 pairs of Common Terns appeared early in the season, they quickly abandoned the site. Presumably many relocated to the immense colony at Monomoy-South, Chatham. Nesting at New Island in Eastham/Orleans was unproductive on account of Great Horned Owl predation. Another chronically unproductive site usually beset with owl problems, Gray’s Beach, Yarmouth, reportedly experienced some production this year. Despite these trouble spots, 81% of all the Common Terns in the state, which were concentrated at three sites-- Monomoy-South in Chatham, Ram Island in Mattapoisett and Bird Island in Marion-- experienced good to excellent productivity. Weather conditions during the season were generally benign, except for an unseasonable northeast storm that struck on 6 June, washing out some nests, particularly those of Least Terns at exposed sites.

During the 2000 season, nesting terns were reported from 67 sites out of the aggregate total of 114 sites reported active in at least one year from 1970 to the present. Common Tern numbers declined 6% to 13,340 pairs, reversing seven consecutive years of increase. Roseate Tern numbers, however, increased 17% to 2,124 pairs, marking the first time their numbers have ventured above the 2,000 pair level since 2,023 were estimated in 1979. Since 1970, the highest Roseate Tern estimate was 2,300 pairs in 1972. Least Tern numbers were estimated at 3,276 pairs, down 4% from the year-earlier level. Laughing Gull numbers grew 36% to 1,097 pairs, the first time their numbers have surpassed the 1,000 pair mark since 1991.

Agencies in the cooperative monitoring network continue to be engaged in a number of large projects. The U.S. Fish & Wildlife Service’s Avian Diversity Program at Monomoy National Wildlife Refuge entered its fifth year in 2000. While Common Tern numbers there have soared, 2

Roseate Tern numbers have not responded as well as expected (actually declining to three pairs from 27 in 1999). Superlative nesting at Ram Island, Mattapoisett, along with social factors, may have drawn birds from other sites, including Monomoy. In addition, habitat conditions for Roseate Terns may not be optimal at Monomoy. If the Monomoy Common Tern colony holds together long enough, conditions there—such as dense vegetative cover—may gradually develop and become more attractive to Roseate Terns. In the meantime, Common Terns produced at Monomoy should recolonize and foster growth at new sites, including those where aggressive Common and Roseate Tern restoration efforts are underway. Two of these sites include MassWildlife’s project at Penikese Island, Gosnold (initiated in 1998 after pilot work in 1995) and a new project begun this year at Muskeget Island, Nantucket by The Nature Conservancy, with additional funding support from the Blake Fund and other private sources.

General Methodology

Censusing of terns in Massachusetts is accomplished using “pairs” as the basic census unit. Generally, complete nest counts are made, at some sites corrected using the Lincoln Index. At a few sites, pair estimates may be extrapolations based on partial nest counts or adult estimates adjusted to pairs by multiplying by 0.8. Where nest counts are made, only nests with eggs are counted and the number of nests is converted to pairs on a 1:1 ratio. Estimates of the number of pairs reported and discussed in this summary, unless otherwise noted, are “A-period” estimates made during a standard 5-20 June window. “B-period” estimates, as sometimes referenced herein, are estimates made later than the “A-period” counts and not included in the total pair estimates for the state.

Common Tern

Common Tern numbers, after seven consecutive yearly increases, declined in 2000 to 13,340 pairs at 32 sites. The drop amounted to about 6%, essentially erasing the previous year’s increase. Terns attempted to recolonize Plymouth Beach, but quickly aborted when faced with fox predation. Most of the Common Tern nesting activity northward from Plymouth to the New Hampshire state line continued to be at marginal sites such as flood-prone salt marshes and dilapidated piers and pilings. Portions of the old Central Square Piers in East collapsed in 2000, taking some nests down with it. While there was reportedly some productivity at Gray’s Beach, Yarmouth, the colony at New Island, Eastham/Orleans was—as usual—severely disrupted by Great Horned Owls and there was little or no productivity.

At the Monomoy Islands, Chatham, numbers increased to 6,897 from 5,536 a year earlier, a 26% increase (on top of a 134% increase in 1999). Monomoy National Wildlife Refuge now harbors about half (51.7%) the Common Terns in Massachusetts. Other sites harboring 1,000 pairs included Ram Island, Mattapoisett (2,030 pairs) and Bird Island, Marion (1,880 pairs). Eighty-one percent of nesting Common Terns were concentrated in these three sites and experienced good to excellent productivity. The total number of active Common Tern sites dropped to 32 from 34 in 1999.

3

Six additional sites reporting 100 pairs included New Island, Eastham/Orleans (997 vs. 2,176 in 1999), Gray’s Beach, Yarmouth (684 vs. 953), Haystack Point at the Edgartown end of Sengekontacket Pond (140 vs. 160), Penikese Island, Gosnold (126 vs. 101), Woodbridge Island, Newburyport (120 vs. 240), and Central Square Piers, (114 vs. 176). Note that all these sites except for Penikese registered declines.

Least Tern

The estimated Least Tern population declined 4% to 3,267 pairs in 2000 from last season’s record high of 3,416 pairs. This still goes into the records as our second best year since careful record keeping began in 1970. Given the unstable nature of Least Tern colonies and the difficulty censusing them accurately, the decline is likely within the margin of censusing error. From 1997 onward, estimates have held above the 3,000 pair level. This year’s results reflect continued ideal habitat conditions offset by predation at some sites and a northeast storm on 6 June that washed-out nests at some sites.

The largest colony in 2000 developed, as in 1999, at Dunbar Point (Kalmus), Barnstable, where 817 pairs were estimated. Nine additional sites reported estimates of 100 pairs in 2000 (vs. seven in 1999) including Dead Neck-Sampson’s Island, Barnstable (383 pairs vs. 87 in 1999), Little Beach, Edgartown (237 vs. 0), , Ipswich (220 vs. 220), Barney’s Joy— Little Beach, Dartmouth (138 vs. 61), North River mouth, Scituate (133 vs. 44), Sandy Neck, Barnstable (128 vs. 148), Monomoy-South, Chatham (119 vs. 103), Tuckernuck Island, Nantucket (110 vs. 75), and Great Island, Wellfleet (105 vs. 83). Note that seven out of these nine additional sites carried substantially more pairs than in 1999 and one site had the same number of pairs as in the previous year, reflecting a generally broader distribution of birds among sites in 2000 compared with 1999. Also indicative of this pattern, Least Tern nesting activity was reported from 50 sites this year, up from 44 a year ago.

Roseate Tern

The estimated Roseate Tern population increased to 2,124 pairs in 2000, up 17% from 1,810 pairs last season. This marks the first time that estimated roseate numbers have risen above the 2,000 pair level since 1979 (2,023 pairs). Since 1970, the highest Roseate Tern numbers were recorded in 1972 (2,300 pairs). This season’s strong performance was fueled almost exclusively by dramatic increase (57%) at Ram Island, Mattapoisett where numbers rose to 998 pairs from 630 pairs in 1999. This increase may be attributable to the fact that no winter storms overwashed the island during the winter season. As a result, lush vegetation—ideal for roseate nesting—developed. In addition to ideal nesting cover, the strong numbers were likely also driven by other factors including the absence of any serious predation threats and natural recruitment within the Northeastern population. Also, the possibility that last year’s numbers were underestimated to some degree cannot be ruled out.

Unfortunately, the good news on numbers of pairs was offset by less encouraging progress on other parameters. Essentially 100% of the Roseate Tern pairs this year were concentrated at only two sites—Bird Island, Marion (1,130) and Ram Island, Mattapoisett (988). 4

On outer , only an additional six pairs could be located---three at Monomoy-South, Chatham and three at Nauset-New Island, Eastham/Orleans. Thus there were only four stations with nesting Roseate Terns, down from six in 1999; this is the poorest showing since 1986. Plymouth Beach, long a small but steady roseate station, was abandoned in 1999 on account of fox predation. Restoration efforts at Penikese brought stronger numbers of Common Terns to the site in 2000, but, while Roseate Terns frequented the site, none nested. At Monomoy-South, numbers actually fell to three pairs this year from 27 a year earlier, despite explosive growth in the numbers of Common Terns there. And at Muskeget Island, no nesting roseates appeared this year despite last season’s five pioneering pairs.

But on a positive note, efforts are underway to remedy the fox problems at Plymouth and the difficulties there will eventually be resolved. Despite a poor showing at Penikese, Monomoy and Muskeget Islands, sites are now available to roseates when and if they should decide to move. It has often been remarked that Roseate Terns, faced with predation or disturbance at a site, are quick to move. But on the other hand, the birds seem to stick with places that have worked well for them over time and they are loath to relocate unless circumstances make it absolutely necessary. The good news is that we are in stronger shape with alternative sites than we were just five years ago. In addition, strong Common Tern productivity at Monomoy should assure an increasing pool of young Common Terns to recolonize or pioneer new sites—sites that may ultimately become host colonies for Roseate Terns.

Other Species

An estimated eight pairs of ARCTIC TERNS were found nesting at three sites in the state in 2000, down from nine pairs in 1999. There were three pairs each at Plymouth Beach and at Nauset-New Island in Eastham/Orleans. Two pairs—joined by possibly as many as three late- nesting pairs—occurred at Penikese Island, Gosnold. So far as I have been able to determine, none of the pairs was productive. Single pairs of BLACK SKIMMERS were at Nauset-New Island, Eastham/Orleans and Monomoy-South, Chatham in 2000. Interestingly, as many as four and two additional pairs appeared later at the same two sites, respectively. Unfortunately none of the nesting attempts was productive this year. LAUGHING GULL numbers increased 36% over last year to reach 1,097 pairs (721 at Nauset-New Island and 376 at Monomoy-South). This follows on a 13% increase last season and marks the first time estimated numbers have topped the 1,000 level since 1,285 pairs were recorded in 1991.

I extend my appreciation and thanks to all the agencies and individuals in the reporting network that make these detailed annual summaries possible. Data collected each season contribute to the historical and scientific record and are incorporated into MassWildlife’s Natural Heritage Database. It is through this database that records translate into real environmental action by provisions of the Massachusetts Wetlands Protection Act (MGL, Ch. 131, Sect. 40A) and the Massachusetts Endangered Species Act (MGL, Ch. 131A).

Report prepared by BRADFORD G. BLODGET, State Ornithologist, MassWildlife, Field Headquarters, Route 135, Westborough, MA 01581-3337.Tele: (508) 792-7270 x152. Fax: (508) 792-7275. 12/1 5

Table 1. PRELIMINARY TABULATION OF THE 2000 MASSACHUSETTS TERN INVENTORY. All results expressed in pairs. Data are collected for all species for the period 5-20 June. Colony numbers follow or are adapted from Erwin and Korschgen (1979). Numbers in parentheses reflect numbers of pairs recorded outside the census period ("B-counts") and are not included in the total pairs.

COLONY COLONY NAME, TOWN Censusing NUMBER Agency1 ROST COTE ARTE LETE BLSK LAGU 324000 Miscellaneous sites, map 324 --- 324007 Woodbridge I., Newburyport USFWS 120 324007.1 Blackwater River Group, Salisbury3 --- 324007.2 Chaces I., Newbury2 USFWS 324008 Plum I. River Group, Newbury (marshes-incl. Pine I., Little Pine I. and USFWS 5 Jericho Creek)4 324009 Parker River Group (marshes)2 USFWS 324009.1 Plum I. Beach, Newbury-Rowley-Ipswich USFWS 13 324010 Roger I., Ipswich2 ECG 324010.2 Bagwell I., Ipswich ECG 19 324010.3 Rowley Salt Marshes ECG 30 324010.4 Lords I., Ipswich ECG 7 324010.5 Ipswich Salt Marshes ECG 6 324011 Crane Beach, Ipswich TTOR 2 220 324038 Tinker's I., Salem MAS 35 324038.1 Bridge, Lynn-Revere Zendeh 44 324040.1 , Everett/Boston Zendeh 7 324040.3 Belle Isle Marsh, Boston2 Zendeh 6

COLONY COLONY NAME, TOWN Censusing NUMBER Agency1 ROST COTE ARTE LETE BLSK LAGU 324040.6 Central Square Piers, East Boston Zendeh 114 324042 Snake I., Winthrop Zendeh 12 (4) 324042.1 Logan Airport, Boston Smith 11 324049.1 Lovell I., Boston2 MAS

324052.2 Rainsford I., Boston MAS 35

324053 Hog I. Pier ("Spinnaker I."), Boston MAS 75 324057 North R. Mouth, Scituate MAS 2 133 324058 Duxbury Beach, Duxbury MAS 18 324060 Wood End-Long Point Area, NPS 40 Provincetown 324061 Race Point Light Area, Provincetown NPS 53 324062 Race Point CG Station, Provincetown2 NPS 324062.1 Mission Bell, Provincetown NPS 70 324062.2 Tasha's Area, Provincetown NPS 42 324062.3 Beach Point, Pilgrim Beach, P’town MAS 8 324063 High Head, Truro NPS 47 352000 Miscellaneous sites, map 3524 --- (1)4 352001 Plymouth Beach, Plymouth MAS 16 3 31 352001.1 Ellisville Harbor, Plymouth MAS 4 352002 N. Sandwich Area (Town Beach- MAS 32 Springhill and Old Harbor ) 7

COLONY COLONY NAME, TOWN Censusing NUMBER Agency1 ROST COTE ARTE LETE BLSK LAGU 352003 Scorton Creek, Sandwich MAS 24 352004 Craigville-Long Beach, MAS Barnstable2 352004.1 Squaw I., Barnstable2 MAS 352005 Dunbar Point (Kalmus Park), Barnstable MAS 1 817 352005.1 Great I., Yarmouth2 MAS 352006 Sandy Neck, Barnstable Barnstable 128 352007 Gray's Beach, Yarmouth MAS 684 5 352008 West Dennis Beach, Dennis MAS 20 24(16) 352009 Nauset-Orleans (Chatham line north to Orleans 1(26) Nauset Harbor Inlet) 352010 Nauset-New Island, Orleans NPS 3(1) 997 3 1(4) 721 352011 Nauset-Eastham(" Guard Beach" & NPS "Plover I.") 12 352012 Marconi Beach, Wellfleet NPS 19 352012.1 Pamet Harbor Bar, Truro MAS 20 352012.2 Great I.-Jeremy Pt., Wellfleet NPS (5) 105 352013 Nauset-Chatham (incl. N. & S. Beach I.) MAS/DFW (30) 352013.1 Tern I., Chatham2 MAS 352014 Harding's Beach and Point, Chatham2 MAS 352015 Monomoy-North, Chatham USFWS 11 352016 Monomoy-South, Chatham USFWS 3 6,886 119 1(2) 376 8

COLONY COLONY NAME, TOWN Censusing NUMBER Agency1 ROST COTE ARTE LETE BLSK LAGU 352017 Dead Neck-Sampson I., Barnstable MAS 49 383 352017.1 , Mashpee2 MAS 352018 South Cape Beach-Waquoit, Mashpee2 DEM 352018.1 Washburn I., Falmouth2 DEM 352020 Great Point (including "The Galls"), TTOR 8 Nantucket 352021 Coskata-Coatue, Nantucket TTOR 25(1) 352021.1 Squam Head & Pond, Nantucket2 NCF 352022 Quidnet (including Sesachacha Pd.), MAS Nantucket2 352023 Siasconset (Sankaty-Low Beach), NMD 70 Nantucket NLB 352023.1 Tom Nevers Head, Nantucket NMD 52 352024 Quaise, Nantucket MAS 60 352025.1 Surfside, Nantucket2 352025.2 Cisco Beach, Nantucket2 NCF 352025.3 Eel Point, Nantucket2 NCF 352026 Esther I.-Smith Pt., Nantucket2 NMD 352027 Tuckernuck I., Nantucket Veit 110(30) 352028 Muskeget I., Nantucket Veit 16(39) (10) 352030 Cape Poge Elbow, Edgartown2 TTOR 9

COLONY COLONY NAME, TOWN Censusing NUMBER Agency1 ROST COTE ARTE LETE BLSK LAGU 352031 Little Neck, Edgartown2 TTOR 352031.1 East Beach-Dike Bridge, Edgartown2 TTOR 352032 , Edgartown TTOR 8 352033 Norton Beach ("Katama"), Edgartown2 Dukes Co. 352033.1 Edgartown Great Pd., Edgartown2 SMF 352034 Sarson I., Sengekontacket Pd., Oak MAS Bluffs2 352034.1 Haystack Pt., Sengekontacket Pd., SMF 140 Edgartown 352034.2 Little Beach, Edgartown SMF 237 352035 Sylvia State Beach, Oak Bluffs Dukes Co. 10(5) 352035.1 Harthaven Beach, Oak Bluffs2 SMF 352036 Watcha Pd., West Tisbury2 SMF 352036.1 Oyster Pd., Edgartown2 SMF 352037 Quansoo Area (Tisbury Great Pond, W. SMF Tisbury & Black Point Pond, Chilmark)2 352037.2 Chilmark Pd., Chilmark2 SMF 352038 Lobsterville (incl. "Dogfish Bar"), Gay SMF 8 Head 352038.1 Menemsha Pd., Gay Head-Chilmark SMF (encompasses Edys I., Chilmark)2 352038.2 Stonewall Beach, Chilmark SMF 8 10

COLONY COLONY NAME, TOWN Censusing NUMBER Agency1 ROST COTE ARTE LETE BLSK LAGU 352038.3 Long Beach, Gay Head & Squibnocket SMF Beach, Chilmark2 352039 Nomans Land, Chilmark3 USFWS 352040 Tashmoo, Tisbury SMF 16 352040.1 Eastville Beach, Oak Bluffs Dukes Co. 65(25) 352040.2 Lamberts Cove-James Pd., W. Tisbury2 SMF 352041 Nashawena I., Gosnold MDFW 3 352041.1 Pasque I., Gosnold MDFW 8 352042 Penikese I., Gosnold MDFW 126(60) 2(3) 352042.1 Cuttyhunk I., Gosnold MDFW 2 22 352043 Ram I., Mattapoisett MDFW 988 2,030 1 (141) 352043.1 Strawberry Pt., Mattapoisett2 MDFW 352044 Fish I., Fairhaven2 MDFW 352044.1 Long I., Fairhaven3 MDFW 352044.2 West I., Fairhaven2 LCE 352044.3 Winsegansett Hts., Fairhaven2 LCE 352044.5 So. Shore Marshes WMA, Little Bay, MDFW 7 Fairhaven 352045 Bird I., Marion MDFW 1,130 1,880 (150) 11

COLONY COLONY NAME, TOWN Censusing NUMBER Agency1 ROST COTE ARTE LETE BLSK LAGU 352045.1 Salter's Pt. and Pd., Dartmouth2 LCE 352045.2 Demarest Lloyd State Park, Dartmouth2 LCE (1) (32) 352046 Barney's Joy-Allen's Pd.-Little Beach, LCE 138 Dartmouth 352046.1 Gooseberry Neck, Westport2 LCE 352047.1 Speaking Rock, Westport2 LCE 352048 Cockeast Pd.-Acoaxet, Westport3 LCE 352048.1 Richmond Pd., Westport2 RINHP 352048.2 Horseneck Beach, Westport2 LCE 352054.1 Bay Point, S. Swansea2 Waring

TOTAL 2000 NESTING PAIRS (P): 2,124 13,340 8 3,267 2 1,097

TOTAL 1999 NESTING PAIRS: 1,810 13,979 9 3,416 3 804

PERCENT + (-) FROM 1999: 17 (6) (11) (4) (33) 36

TOTAL 2000 NESTING SITES: 4 32 3 50 2 2

1 in addition to the names of towns and individuals, the following abbreviations are used: DEM=Massachusetts Department of Environmental Management; DFW=Massachusetts Division of Fisheries & Wildlife (MassWildlife); ECG=Essex County Greenbelt Assoc.; LCE=Lloyd Center for the Environment; MAS=Massachusetts Audubon Society—Coastal Waterbird Program; NCF=Nantucket Conservation Foundation; NLB=Nantucket Land Bank; NMD=Town of Nantucket Marine Department; NPS=National Park Service; RINHP=Rhode Island Natural Heritage Program; SMF=Sheriff’s Meadow Foundation; TTOR=The Trustees of Reservations; and USFWS= Fish & Wildlife Service. 2 no nesting activity found 3 colony not checked in 1999 4 Dowse’s Point, Barnstable Data compiled by BRADFORD G. BLODGET, State Ornithologist, Massachusetts Division of Fisheries & Wildlife, Field Headquarters, Route 135, Westborough, MA 01581-3337. Tele: (508) 792-7270x152. Fax: (508) 792-7275. bblodget\data\00t-sum