More details on recent Labrador polar bear sightings – almost EATEN déjà vu

Finally, we have further details from the CBC on the report earlier this week of polar bears seen in several coastal Labrador communities, in what must be some of the earliest sightings ever documented. Statements from witnesses reveal that the polar bears weren’t just on shore, they were brazenly prowling around people’s homes looking for food – in the dead of winter.

Polar bear on ice_SARA registry webpage_gov Can

UPDATE: 7 February 2016. In an interview earlier today (listen here), one of the oddest explanations I’ve heard for the recent polar bear sightings was offered by Newfoundland and Labrador Minister responsible for wildlife Perry Trimper. He stated: “…climate change does play a roll here [in the increased number of sightings].” 

I’ve listened to the interview six times and still have no idea what he’s talking about. This is not a range expansion caused by “climate change” – polar bears have always come as far south as Newfoundland. In fact, they used to be far more common than they have been over the last centuries (known from at least the 1500s in Newfoundland and the 1700s in Labrador, although there is no evidence they ever stayed over the summer). But polar bears did not formerly, as far as I am aware, come ashore in frightening numbers in January/early February.

When the size of a population declines, its range contracts: the simplest explanation for seeing bears onshore this early in the season is that there are many more bears and that the few late 20th century records of polar bear sightings in this region reflected an over-hunted population that has only recently recovered. See below for more (and PolarBearScience post here).

UPDATE: 19 February 2016. A horse was killed by a polar bear in SW Greenland on 18 February, the second incident in two days of polar bears causing problems onshore in Greenland. Details here.

There were apparently no photos taken of any of the bears sighted (bear above is from elsewhere; even the CBC resorted to photos from previous years) and none of the witnesses mentioned the condition of the bears (whether fat or thin).

Oddly, the CBC report (6 February 2016) glosses over how unusual the timing of these visits are.

It turns out there was a polar bear on Black Tickle two weeks prior to the sightings last week, in mid-January. Mid-January! The bear ripped apart a water line and “tried to dig up the septic tank,” although this appears not to have been reported at the time. The same house had another polar bear visitor at the end of January.

Said the conservation officer in Black Tickle:

It’s getting a little bit too close when they start coming around your houses.

 EATEN déjà vu? Not quite. But as far as I can tell, multiple incidents of obviously hungry polar bears onshore in January/early February is not something these communities have ever experienced – because in the last 300 years, there’s probably never been as many polar bears in this region as there are now.

The CBC story states that the second visit of a polar bear to the house of Black Tickle residents Kate Turnbull and Tim Coombs came on the evening of 1 February, as a bear peeked in a kitchen window at Tim while he was cooking dinner. In another Labrador community (Charlottetown) a day earlier (31 January), a bear snacked on dog food meant for Dwayne Russell’s sled dogs:

“Wildlife officers fired a couple of bangers at him — “rubber bullets or whatever,” Russell said.

“I think it was the second or the third one before he even noticed that they struck him, and he took off.”

Russell said the bear came back but the second time kept its distance in the woods.

Like the one spotted on Turnbull’s property, this bear wasn’t captured and is believed to have headed towards the Atlantic Ocean.” [my bold]

Regarding the rarity of these sightings, it seems the CBC reporters decided not to dig through their own archives but accepted a local explanation for the events:

“While it is common for polar bears to visit Labrador, they usually arrive in the spring while making their way back north, sticking to the shoreline or out on the ice.

Keefe [Jeffrey Keefe, a sergeant with the Canadian Rangers in Black Tickle] said they generally do not venture so close to houses.

“The only thing I can figure is that there’s a lot of sea ice, so I guess they’re on the move earlier … they just wait around for the sea ice so they can get out to the seals.” [my bold]

Sorry, that last sentence makes no sense to me: Labrador polar bears don’t spend the winter on land waiting for sea ice to come to them. The bears were on the ice already: they came from the north, moving with it as it expanded south. What the bears are waiting for is the birth of seal pups (more on that later).

The fact is that there’s not more ice than usual off Labrador this year – it’s about average. There was more ice than usual for this time of year in 2014 but no reports of polar bear sightings in Labrador and northern Newfoundland.

See the ice maps and graphs below for late January/early February, starting with a graph that compares the ice extent off southern Labrador for the week of 29 January between 1969 and 2016, with the long-term mean and average marked:

Davis Strait S Labrador same week 29 Jan 1971-2016

2016 sea ice at 1 February below – average ice extent, multiple sightings of polar bears onshore in southern Labrador in January/early February:

Canadian Arctic Feb 1 2016_CIS

2014 sea ice at 31 January below – lots of ice, no January/February polar bear sightings reported in Labrador:

Sea ice extent Canada_2014 Jan 31_CIS

2010 sea ice at 31 January below – low sea ice off Labrador, no January/February polar bear sightings reported in Labrador or northern Newfound:

Sea ice 2010 Labrador 31 January_MASIE

Last year there were bears sighted on Black Tickle on 23 February (see 2015 map below) – almost a month later than this year’s multiple sightings – lots of ice then also. Prior to that, visits to Labrador and Newfoundland are in April/May, occasionally later or slightly earlier (late March), with a few rare exceptions.

Sea ice Canada 2015 Feb 22_CIS

From a 2015 CBC report:

“Jeffrey Keefe estimates there were about nine polar bears in the vicinity of Black Tickle on Monday [23 February 2015], marking one of the earliest times yet that the large carnivores have been spotted in the coastal Labrador community.” [my bold]

If there is evidence of polar bears onshore in January and early February from previous years that I’ve missed, I’d sure like to hear about it (and will add it to this post).

How about a lot more bears as an explanation for these winter sightings?

It’s what I anticipated in my novel – I just didn’t expect to see evidence of it so soon.

By 2007 (the last time they were counted), the population of polar bears in the Davis Strait subpopulation (see map below) had increased substantially over the 1993 count: numbers were up to about 2,158 bears compared to about 1,400 previously. Nine years have passed since then, time enough for the population to have increased even more – especially given the huge numbers of harp seals (estimated in 2014 at 7.4 million (range 6.5 – 8.3m) that have their pups on the sea ice of the Labrador Sea (not to mention the 100,000 or so hooded seal pups that are born in the same area). Well-fed polar bears have more cubs per litter and those cubs survive better.

map-DavisStrait

Boundaries of the Davis Strait polar bear subpopulation, courtesy IUCN Polar Bear Specialist Group.

Biologists speculated back in 2007 that polar bears in Davis Strait might have reached their carrying capacity: the theoretical limit of the local habitat to support them. However, they perhaps didn’t account for the incredible numbers of harp seals that were then available to feed the bear population. In 2004, a harp seal survey in the Northwest Atlantic placed the population size at about 5.7 million animals (range 4.4-6.9m) – by 2008, the estimate had risen to 8.3 million (range 7.5-8.9m), only to decline somewhat to the 7.4 million figure by 2014. Most of these seals have their pups north of Newfoundland and off the southern Labrador coast (called the “Front”).

It appears to me these recent polar bear sightings may be evidence that many more bears exist in this area and they are staging off the Labrador and Newfoundland coasts waiting for the birth of harp and hooded seal pups: the 12th of March is the peak date for harp seal pups in this area, with some early births to be expected perhaps a week or so before that (that’s why EATEN: A novel is set in early March), and hooded seals a bit later.

That means we are at least a month away from there being abundant fat seal pups for Davis Strait polar bears to eat. So unless the bears can catch a hapless adult or a naïve young seal from last year’s crop, they are going to be without food for many more weeks to come.

It also means there could be more hungry bears coming ashore on Labrador and northern Newfoundland in the next few weeks – far closer to the scenario I imagined in EATEN than I expected to see in 2016.

[Nothing more on the even earlier sighting (26 January 2016) of polar bear tracks in Tilting, on Fogo Island, northern Newfoundland and no other details about the polar bear visits to the other Labrador communities mentioned in last week’s CBC report: Norman Bay (just north of Charlottetown) and the Wunderstrands (near Cartwright)]

Black-tickle-map-Labrador 2016

 

References consulted
Peacock, E., Taylor, M.K., Laake, J., and Stirling, I. 2013. Population ecology of polar bears in Davis Strait, Canada and Greenland. Journal of Wildlife Management 77:463–476. http://onlinelibrary.wiley.com/doi/10.1002/jwmg.489/abstract?deniedAccessCustomisedMessage=&userIsAuthenticated=false

DFO Harp seal status report 2014 (estimated from 2012 data). Pdf here.

DFO Harp seal status report 2011 (using 2008 data). Pdf here.

DFO Harp seal status report 2009 (using 2004 data). Pdf here.

DFO Harp and hooded seal status report 2014.   Pdf here.

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