THE BROTHERS, Yarmouth County, Nova Scotia

SUMMARY OF OBSERVATIONS AND CONCLUSIONS:

In 1999, the number of tern nests on The Brothers declined again from that of the previous year. There were 399 (down from 452) tern nests on North Brother (N. Brother). Sixty-one of these were Roseate Tern nests. In 1998 there were 59 Roseate Tern nests, up from 54 in 1997.

In 1998 there were 151 tern nests on South Brother (S. Brother); in 1999, there were none. On June 7 when the census was taken, about 60% of the terns on N. Brother appeared to be Arctics. Later in the season the percentage of Arctic Terns appeared to drop noticeably. A crippled Great Black-backed Gull is believed to be at least partly responsible and thought to have depredated many Arctic Tern nests on the north and northwest beach of N. Brother. It was removed from the island on June 19. One Great Black-backed Gull's nest was removed from S. Brother.

In early July a discrepancy was noticed on the ages of tern chicks. Almost all the Common and Arctic Tern chicks were either hatchlings or chicks over 2 weeks of age. There was an unusual high number of uneaten Butterfish/Dollarfish (Peprilus triancthus) at Common Tern chick feeding sites. In late July, Arctic Tern eggs which were unhatched on July 9 were still unhatched. By then, there were no more fresh uneaten Butterfish/Dollarfish found on the island.

A visit to N. Brother on Aug. 20 revealed many unhatched and spoiled Roseate Tern eggs. There was an overgrowth of Mustard and Morning Glory smothering the island, and nesting sites were difficult or impossible to find.

There was a substantial increase in the number of tern nests on Pinch Gut I. in 1999. The numbers grew to 350 from 186 in 1998. About 90% of the terns there were Commons; the remainder, Arctics.

My suspicion is that the decrease in the total tern nest number on The Brothers and the increase on Pinch Gut I. are related. One Red-breasted Merganser nest with 10 eggs and over 20 Common Eider nests were found on Pinch Gut I. on June 7.

20 Arctic Tern Nests were found on Flat I. on June 5 and there were perhaps 10 Arctic Tern nests on Round Island. Ten Arctic Tern nests (including three 2.5 week old chicks) were found on Gannet Rock, July 12. There were 6 Common Tern nests on Île Chespêque on June 6, and a few Common and Arctics probably nested on The Thrum.

Royden D'Eon, at his aquaculture pen near N. Brother, reported seeing small numbers of crows on the Brothers before the arrival of the terns. Action was undertaken on May 13 to rid the island of Crows; the action was successful and Crows were not a problem there in 1999. The aquaculture pens were dismantled during the summer.

It has been disappointing to find so many unhatched and spoiled Roseate Tern eggs on N. Brother in 1999. The Roseate Terns nested well, the weather was generally good, there was little depredation, and a very limited human presence on the island. I am open to comments or suggestion on how to make these islands more productive. It would surprise me if 20 Roseate Terns fledged this year from the record number of 61 nests. Fledgling success should be 2 or 3 times better than this. STILL A RELATIVELY POOR YEAR FOR HATCHLING AND FLEDGLING SUCCESS ON N. BROTHER

OBSERVATIONS:

April 30, 1999 - My son, Nigel, and I fixed up a number of Roseate Tern nest shelters on the Brothers. The Brothers are two tiny islands about 1 km west of Lower West Pubnico, Nova Scotia, Canada. No Terns were seen. There was one Common Eider nest with 4 eggs on The Southern Brother (S. Brother).

Harold d'Entremont reported 2 terns at East Pubnico.

Roseate Tern nest shelters on N. Brother

A few washed up lobster crates were added to last year's number of shelters by knocking off a board or two, turning them over at a suitable location and placing several heavy stones on top so they would not be moved by the elements. Other washed up boards and plywood were propped up and weighted down with stones to provide additional Roseate Tern nesting shelters.

On S. Brother, located about 1 km to the south of the Northern Brother (N. Brother), we transformed another couple of washed up lobster crates into Roseate Tern nest shelters. The nesting area on this island is perhaps 15 percent as large as on N. Brother.

There were no gull nests to be removed from either island.

May 1, 1999 - 5 Terns reported in Lobster Bay by Lobster fisherman, Phillip LeBlanc.

May 3, 1999 - Kirk Atkinson reported 30 terns 4 miles west of the Brothers.

May 6, 1999 - Robert Nickerson reported about 50 terns above N. Brother.

May 8, 1999 - Andrew D'Eon checked out the Brothers with me. There were a dozen or so Common and Arctic Terns in the air. Still no gull nests to remove. We brought with us 10 more nest boxes to place on the island. There were 3 crows on N. Brother as we arrived. Royden D'Eon, at his aquaculture pen near N. Brother, reported seeing small numbers of crows on the Brothers all this spring. There was a second Common Eider nest on S. Brother; this one with 5 eggs.

May 13, 1999 - Visited the Brothers with Andrew and Rory D'Eon. There was about 200 Common and Arctic Terns on N. Brother. Lobster fisherman, Réal d'Entremont reported as many as 500 terns there earlier in the morning. We saw one crow on N. Brother. No Roseate Terns yet.

Action was undertaken to prevent a repeat of the crow problem of 1998 on the N. Brother tern colony when a crow or crows collected and ate several hundred tern eggs and contributed heavily to the extremely low fledgeling success - 2 fledged Roseate Terns from 59 nests.

May 15, 1999 - Quick visit to N. Brother revealed about 500 terns and no crows. There were still no signs of Roseate Terns.

May 17, 1999 - 2 crows which had frequented N. Brother will be there no more.

May 22, 1999 - No Roseate Terns at The Brothers yet. Only about 200 Common and Arctic Terns in the air. Two Common Tern nests with one egg each in the grass on N. Brother. We found a third Eider nest with 4 eggs on S. Brother. Crew - Nigel, Andrea and Adam Atkinson, and Alix d'Entremont.

We then continued to East Money Island (a.k.a. "Île à Sam") and found about 100 Double-crested Cormorant nests from last year as well as 6 Common Eider nests and about 25 Great Black-backed Gull nests.

Lester D'Eon reported 2 tern nests on Île Chespêque (a.k.a "Rat Island"), Pubnico Harbour.

May 29, 1999 - Quick tern nest count on N. Brother. We counted 220 nests, including 3 Roseate Tern nests. Crew - Lester, Andrew and Josette D'Eon, Jean-Bernard d'Entremont, and my daughter, Ingrid.

June 5, 1999 - There were 20 Arctic Tern Nests on Flat I. No hatched tern eggs yet. Some Common Eider nests on Flat I. had hatched. There were some Arctic Terns above the southern beach of Round Island; possibly up to 10 nests there. We saw 1 Puffin at Round Island and about 25 at Noddy I. Crew: - Raewyn and Mark (visiting fron New Zealand), Celine LeBlanc, Anna-Claire and Tanya Nickerson.

June 6 1999 - A quick Roseate Tern nest count on N. Brother with Ronald d'Entremont and his dad, Olen, found 20. There were no signs of egg or nest depredation. The weather had also been good for egg incubation.

Lester D'Eon counted 6 Common Tern nests on Île Chespêque, Pubnico Harbour.

June 7, 1999 - Tern nest count on Pinch Gut I. (Île-aux-maringouins) revealed 303 mostly Common Tern nests. Actual estimate closer to 350 nests. Species mix approximately 90% Common, 10% Arctic Terns. No Roseate Terns seen or heard.

There were 8 Common or Arctic Terns on The Thrum harassing a single Great Black-backed Gull. We did not make a landing there.

On N. Brother we counted 399 tern nests, 27 of which were Roseate Tern. The majority of the others, perhaps 60%, were Arctic Tern. The number of Common Tern nests was down from previous years; at the same time the number on Pinch Gut I. was up by almost the same number. There were no tern nests on S. Brother. One Great Black-backed Gull's nest with 2 eggs was removed fron S. Brother.

These nest counts were undertaken with the help of Canadian Wildlife Service Atlantic Region biologists, Andrew Boyne and Dedreic Grecian.

Other noteworthy observations: There was one Red-breasted Merganser nest with 10 eggs and over 20 Common Eider nests on Pinch Gut I. One Greater Shearwater was observed from a few metres about 2km northwest of Abbott's Harbour.

Tern Nests Numbers on The Brothers - 1999

	N. Brother	S. Brother	totals
June 7, 1990	302	28	330
June 11, 1991	441	13	454
June 11, 1992	413	0	413
June 9, 1993	367	0	367
June 8, 1994	380	0	380
June 14, 1995	457	0	457
June 16, 1996	554	12	566
June 12, 1997	630	120	750
June 11, 1998	452	151	603
June 7, 1999	399	0	399

June 17, 1999 - One tern nest with one egg remaining on Île Chespêque. It was still being incubated. I went to this island with Lester D'Eon and my daughter, Ingrid, in the Zodiac. We found a recently dead female Common Eider on the island. Lester removed a band from its leg.

June 19, 1999 - Roseate Tern nest count on N. Brother upped the nest number to 43. There were 2 Roseate Tern hatchlings (a day or 2 old). No dead tern chicks were found; two headless adult Common or Arctic terns were also found, both in deteriorated condition. All eggs in nests appeared or felt as being incubated. One Common or Arctic Tern chick was being severely attacked by tiny black ants. Its sibling in the nest appeared allright.

PROBLEM - Upon our arrival to N. Brother, the terns were harassing (diving down upon) a Great Black-backed Gull with a drooping wing. Arctic Tern nests on the north and northwest beach were gone (no chicks or eggs). There was one depredated tern egg on this beach. The rest of the island looked in great shape. Lots of less-than-a-week old tern chicks and incubating eggs.

The gull was chased out to sea and captured by Raoul d'Entremont in the boat and then taken and released at Abbott's Harbour.

Crew - Lisette and Raoul d'Entremont.

June 26, 1999 - Roseate Tern nest count update on N. Brother. GREAT NEWS! Roseate Tern nest number upped again to 59, including 8 chicks. One of these, a 5 or 6 day old chick was dead. Lots of Roseate Tern activity. Many eggs still unhatched but still being incubated. Only a few cold eggs on N.`Brother and low chick mortality, so far. Eight dead chicks were counted. The island seemed to be in great shape.

There were still a lot of unhatched Common and Arctic Tern eggs. My crew: David Cornman and my daughter, Ingrid.

July 9, 1999 - Nigel and I brought Tony Diamond and his wife Elizabeth to N. Brother to band some Arctic Tern chicks. We only managed to fine two chicks to band. Eight Roseate Tern chicks were found and we counted about 25 Common Tern chicks. Almost all the Common and Arctic Tern chicks were 2 weeks old or more, yet there were many unhatched eggs which still appeared as being incubated. There were virtually no chicks between the ages of hatching to 2 weeks, except for some Roseates. A small number of tern chicks were dead. There was an unusual high number of uneaten Butterfish/Dollarfish (Peprilus triancthus) at Common Tern chick feeding sites. Several dozen Common and/or Arctic Tern chicks had already fledged.

One Spotted Sandpiper nest with 2 eggs and 2 hatchlings was found. A Willet was also suspected as having a nest on the island.

Tony Diamond is a Biology professor at the University of New Brunswick, Fredericton.

Two additional Roseate Tern nests were found on N. Brother bringing the total to 61 for 1999.

Total 61 Roseate Tern nests - A NEW RECORD