Longtail numbers are under threat by gangs of crows that have raided nests, destroying eggs and eaten hatchlings.Alarms were first raised in 2009, when 50 Longtail egg remains were found on the Castle Point property at the end of the Tucker’s Town peninsula.A Department of Conservation Services investigation discovered the eggs had been taken by one group of four crows. The crows were observed a number of times with downy Longtail chicks in their beaks, which were then killed and eaten. Three of the crows were destroyed and hatchling numbers increased as a result.But a new group of crows moved onto the Nonsuch Island/Castle Harbour area this year, and Longtail eggs are once again a target.A Government spokesman said: “On one island alone, over 15 nests were robbed out of a total of 40 on the island, and tallies of all eggshells found show that between 75 and 100 nests were robbed, with some of the islands having almost half of the active breeding pairs losing their only chance to produce a chick this year.“This destruction was caused by only six or so crows, and as crows readily learn new feeding techniques from other crows, if this number was allowed to grow, it could endanger the entire nesting population of the much-beloved Longtail on Bermuda.”Three of the crows have now been “removed” by pest control officers, but officials are still concerned that the problem could spread.“At this time the problem is location-specific due to the relatively narrow concentrations of Longtails in specific nesting areas and because Crows are territorial,” Director of Conservation Services Drew Pettit said.“However the great concern is that the problem could potentially grow quickly.”The American Crow — which is listed as a pest species — probably came to Bermuda in 1838, when a pair was introduced as pets from Nova Scotia.“As each nesting pair of Longtails generally produce only one egg annually, this represented a major impact on the population of Longtails nesting in the Castle Harbour area, which contains one of the largest nesting concentrations for this species of seabird in the North Atlantic Ocean,” said Senior Conservation Officer Jeremy Madeiros.“The concern was that this group of crows was specifically targeting Longtails, pinpointing the nesting sites by watching to see which holes they were flying to in the cliffs and then mobbing the adults to chase them out of the nests and snatch the eggs or young chicks.”Yearly monitoring, and if necessary, continued control of crows will be carried to prevent serious impact to Bermuda’s internationally important Longtail population and agricultural interests.