July 1890.] 



AND OOLOGIST. 



99 



Isle Royale. 



Some ten miles north-east from tlie eastern 

 (Mul of Isle Itoyale lies a group of rocks, the 

 largest scarcely two acres in extent, looking in 

 the distance like three black mounds resting 

 on th(^ blue waters of Lake Superior. 

 For a number of years past this has been 

 the principal nesting place in the north- 

 west, of the American Herring Gull, and ow- 

 ing to its isolated situation and inaccessibility 

 has been visited, aside from the few fishermen 

 who supply themselves with fresh eggs each 

 year, by less than half a dozen people the past 

 six years. 



On May 22nd my brother and myself were 

 dropped from the fish boat Dixon in a small 

 I'owboat at the north-east end of Isle Koyale 

 intending to risk the row across the ten mile 

 space to Gull Islands, but tempestuous weather 

 ])revcnted and we camped (m the rocks until 

 the 2r)th, when we engaged the services of a 

 Finland fisherman and his staunch sailboat for 

 the trip. Starting at daylight we reached the 

 rocks after a three-hours sail. 



Before the detail of the rocks are seen 

 there is apparently no sign of life, but as we 

 drew near, the rocks, as our fislierman ex- 

 l)ressed it, looked as though they were covered 

 with Snowbirds, distance dwarfing the Gulls 

 in the clear air, but drawing still nearer they 

 increase to their full size and present abeauti- 

 full appearance on the black rocks. A half 

 dozen came out a half mile to meet us with 

 loud cries as a protest against this intrusion, 

 and by the time we had landed at the only 

 available spot on the islands the whole colony 

 of over a thousand (iulls were either circling 

 above with loud cries or resting on the water 

 a short distance away. 



The ledge of rock composing the islands is 

 inclined at an angle of 45^, and affords numer- 

 ous deep niches which have become filled with 

 guano, and form level places for the nests 

 which were often formed by hollowing out a 

 place in this deposit, but the majority of the 

 nests were made of a peat-like substance, the 

 roots or fibres of moss and coarse grass mixed 

 and matted together, and where they had not 

 been disturbed by the fishermen, contained 

 three eggs with incubation well started at this 

 date. Some of the birds showed great lack of 

 judgment in the location of their nests; one 

 containing three eggs was located on a narrow 

 gravel beach ten feet below, where the last 

 north-easter had lodged tlic drift wood, and 

 there were some thirty nests in this little patch 



of drift wood itself. But a still greater lack of 

 judgment was shown by at least four differ- 

 ent Gulls who had placed their nest on top of the 

 huge icebergs formed on the rocks by the dash- 

 ing of waves last winter. The few warm days 

 had already honeycombed the mass and melted 

 away from around the nests leaving it resting 

 on a white pillar of ice nearly two feet above 

 the surrounding berg with one side of the nest 

 already to]ipling down. A few more warm 

 days would send the whole mass into the 

 lake. 



We secured many beautiful sets of eggs, 

 which show a wide range of marking. 



The rocks seem to be well tenanted, besides 

 the Gulls, numerous Warblers and small birds 

 hung around the scraggly biush at one end 

 of the rock, and a Sparrow dragged its wings as 

 it fiuttered along the ground, probably from its 

 nest. A pair of Hawks, which we did not iden- 

 tify, occupied the ends of two u])right posts left 

 by the United States surveyors years ago, and 

 the ground beneath was coveied with pellets 

 which they had disgorged. During the season 

 of migration the smaller birils reach these 

 rocks completely exhausted and these Hawks 

 gorge themselves on the helpless victims. 



On approaching the island we saw three 

 small birds fiuttering towards it some little 

 distance apart. The Hawk came out, seized 

 one, deposited it somewhere on the rocks 

 then whirled about and secured the next and 

 deposited it with the other and finally secured 

 the third. A shelving, mossy place about four 

 feet square seemed to be a perfect slaughter 

 pen for small birds; the bushes and rocks 

 around were covered with feathers scattered by 

 the winds, while this particular spot was cov- 

 ered with the larger feathers and ends of wings 

 of .all kinds of smaller birds with a great many 

 Flicker feathers mixed in to give it color. 

 Scratching with a stick disclosed nearly an 

 incli in depth of wet, matted feathers. The 

 destructit)n of small birds by this one pair of 

 Hawks must have been enormous. After the 

 season of migration is over they pluck an 

 occasional young Gull from its nest, and the 

 fishermen claim that it attacks the old Gulls 

 themselves when hungry. We found their nest 

 on the highest part of the rocks containing 

 two fresh eggs, the fisherman having destroyed 

 a set of four three weeks previously. Of the 

 Gull nests from which eggs were taken the 

 same time, we found but a single fresh egg, 

 showing that they had just commenced to lay 

 the second set. Such eggs were much smaller 

 than the first laying. We saved a few skins of 



