Breeding populations of diving birds rose after certain fisheries that relied on curtain-like gillnets closed in 1992. Paul Regular at the Memorial University of Newfoundland in St John's, Canada, and his team analysed seabird census data collected before and after the collapse offish populations prompted the closure of cod and salmon fisheries in eastern Canada. The team compared the numbers of diving birds such as auks and gannets, which can get entangled in gillnets, with those of surface feeders such as gulls, which thrive on fishery waste. The number of diving birds increased after the nets were removed, whereas scavenger numbers decreased. In particular, growth in the common murre (Uria aalge, pictured) population was much higher during the 2000s than the 1970s, whereas the herring gull (Larus argentatus) population, which grew in the 1970s, shrank from 2000 to 2010.
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