I read this story quite differently. The fact is that the recoveryof raptor populations over the past forty years has been remarkable. Some may want to claim this is because of the demise in use of DDT,but I am way more inclined to assign causation to the effective endof utterly irresponsible hunting by teenage farm boys. Not only dowe have less said farm boys, but they all know better.
Growing up in Mid Western Ontario back in the sixties, all game wasscant. Yet I was out every day with a rifle in hand patrolling ourfifty hectares of country side with a dog on hand to flush game. This was common and in the two decades that we covered, I saw a deeronce, grouse once and multiple foxes and no end of groundhogs andrabbits. I was looking and catching little.
All that has now changed, not least because it is no longer fiftyhectares but assembled into 500 hectares and the farm boys have beentold off on hunting raptors and most game. Thus the deer are allcrowding back as well as everything else. In the end, it will needmanagement protocols to control their populations if not so already.
Record numbers of owls at a refuge in the Fraser Delta suggestsrecord populations up country. Snowy owls are Arctic adapted tostart with and more reasonably, they are expanding their range.
In any case, Vancouver has large populations of raptors because it isthe focus of migrants from Alaska and BC. It is not unusual to seeflocks of several dozen eagles here.
Record number ofowls and other raptors needing help in Lower Mainland
10 snowy owls amongthe 485 birds treated at Delta rehabilitation centre
By Larry Pynn,Vancouver Sun December 27, 2012
http://www.vancouversun.com/technology/Record+number+owls+other+raptors+needing+help+Lower+Mainland/7750111/story.html#ixzz2GNBNzBH4
A record 485 raptors,including emaciated snowy owls from the Arctic, have been brought tothe two-hectare OWL rehabilitation centre in south Delta so far thisyear.
“We’ve neverbroken 400 before,” OWL founder Bev Day said in an interviewThursday. “It tells you how bad the birds are doing.”
Loss of habitat due todevelopment, including port expansion and the South Fraser PerimeterRoad, as well as conversion of traditional farmland to blueberryproduction have resulted in less prey to go around, Day said.
A total of 10 snowyowls — most of them starving, but also one that flew into a powerline — have been brought to the centre, not just from Delta, butfrom as far afield as Prince George, Pemberton, and Hope. Only onehas survived.
Snowy owls are sodesperate for food they have been spotted as far south as California,Day said.
The survival rate forall 485 raptors brought in this year, including eagles, hawks, owls,and falcons, is about 70 per cent.
People are phoning toreport snowy owls on their house roofs, but Day said people shouldnot be concerned unless the birds are seen on the ground and indistress. Photographers looking for the perfect shot are urged not toharass the birds by approaching too close.
Wet weather can alsomake it more difficult to for the birds to access prey, Day said,adding that raptors with weakened immune systems are also at risk ofcontracting aspergillosis, a lung disease.
She noted thatdevelopment of the South Fraser Perimeter Road includes some goodmitigation measures, but they are no substitute for the 90 hectaresof farmland removed for the $1.2-billion development. “It doesn’treplace everything, but they are working on it,” she said.
Among the mitigationmeasures are wildlife tunnels and the creation of marsh habitat.
The conversion oftraditional farmland to blueberry production also eliminates habitatin which the raptors might otherwise find prey, Day said.Agricultural pesticides — a poisoning risk — are also an issue.
Formed 37 years ago,OWL (owlcanada.ca) receives no direct government funding and isstruggling to make ends meet given the large volume of raptors. Cashdonations are appreciated, as well as contributions of wild game andfish, but not commercially processed poultry or other meats.
Pat Wagar of theMountainaire Avian Rescue Society in Courtenay said the facility hasreceived six emaciated snowy owls, of which only one survived. Amongthe other birds brought in for treatment are a long-eared owl,short-eared owl, and a brown pelican.
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