From Polar Bear Science
Posted on August 12, 2019 |
It’s been a sluggish summer season for polar bear information to hype, so we shouldn’t be shocked native report that polar bears this summer season have descended in town of Kaktovik, Alaska one week sooner than 2017 has morphed into a global story that makes a 2016 analysis report sound like this yr’s information, with headlines trumpeting: “polar bear encounters are growing” as a consequence of an extended open water interval. Nonetheless, it was reported simply two weeks in the past that Alaska has not had a polar bear assault since 1993.
This can be a significantly blatant instance of how the media skew polar bear ‘information’ for public consumption, aided by scientists with a specific message to promote. Not surprisingly, a variety of important information have been unnoticed of this sensationized account, partially as a result of the polar bear specialist the media consulted left these information out of his assertion. That is the type of bias displayed by polar bear specialists that I talk about in my new ebook, The Polar Bear Disaster That By no means Occurred.
The impetus for the unique ‘polar bears onshore’ story out of Anchorage (ADN, Saturday, 10 August 2019) was the report resident of Kaktovik had an in depth name with a bear on Monday 5 August: “Polar bear encounters in Kaktovik aren’t new. However they’re occurring a bit sooner than final yr.”
“She [Annie Tikluk] was about 6 toes away from the bear, she mentioned, and it had two paws on her deck. Then a neighbor ran throughout the road and chased the animal off.”
A USGS polar bear professional who lives in Anchorage was requested to weigh in (my daring):
“However this yr, stories of polar bears in Kaktovik are beginning “a bit bit forward of schedule,” mentioned Todd Atwood, a analysis wildlife biologist who leads the U.S. Geological Survey’s polar bear analysis program.
“We are inclined to see aggregations beginning across the center or third week of August,” mentioned Atwood, who relies in Anchorage.
The bears make their option to land from the Beaufort Sea round this time of yr and await the return of sea ice. There’s quite a lot of variation from one yr to the subsequent when it comes to when the bears come ashore, Atwood mentioned. In comparison with 2017, as an illustration, this yr is simply a few week forward of schedule.”
The ADN story went on to clarify (my daring, hyperlinks in unique):
“Extra vital is the change over an extended time frame. The size of the southern Beaufort Sea’s ice soften season — the time between sea ice breakup in summer season and freeze-up within the fall — “has elevated considerably for the reason that late 1990s,” in accordance with a 2016 analysis paper that Atwood co-authored and that the Anchorage Each day Information reported about when it got here out.
Because the Arctic warms, adjustments in sea ice habitat have coincided with proof that polar bears’ use of land habitat is growing, the analysis discovered.”
So regardless of the unique story clearly stating that Atwood’s work was three years outdated, the subsequent day (11 August 2019) the Related Press out of Anchorage re-jigged the story – “Alaska scientists say polar bear encounters to extend” – to make it sound like Atwood’s examine had simply come out and that these had been new outcomes that had simply been made public.
Though there was a hyperlink within the AP story to the day gone by’s story in regards to the Kaktovik polar bear encounter, there was no hyperlink to the three yr outdated examine or to any of the three yr outdated tales about it. The sensationalized piece additionally added the ‘data’ that Kaktovik “residents have reported [polar bear] sightings as early as Might“.
Atwood’s examine from three years in the past (extra on that beneath) discovered that the few Southern Beaufort Sea polar bears that selected to come back to land in summer season between 2010 and 2013 had spent, on common, 36 days longer onshore than that they had within the 1990s. The authors reported no destructive results from this longer time ashore (in truth, Atwood admitted it might be advantageous) however you wouldn’t know that from yesterday’s AP story, which has been picked up by mainstream information shops throughout North America and around the globe.
Details unnoticed of those tales
Here’s what I wrote on the Atwood examine again in 2016:
Two current research confirmed that whereas extra polar bears got here to land through the ice-free interval within the Southern Beaufort between 2010 and 2013 (and stayed longer than they did within the late 1990s), there have been no destructive results on polar bear well being or survival from spending ~ 2.5 months onshore vs. 1.5 months despite the fact that the bears misplaced weight (Atwood et al. 2016; Whiteman et al. 2015). An identical consequence got here from work within the Chukchi Sea – much less summer season ice meant extra time on shore for a bigger variety of bears however with out destructive results on well being or survival (Rode and Regehr 2010; Rode et al. 2013, 2014).
An earlier paper on polar bears drawn to whale bone piles in Barrow (Heereman and Peacock 2013) discovered that bears visited all by the autumn (beginning in November 2010) and continued into the useless of winter (February 2011).
Kaktovik, Alaska (on Barter Island) has been attracting vital numbers of polar bears ashore in summer season for the reason that early 2000s (Miller et al. 2006, 2015), as have a number of different areas. Most whaling at Kaktovik is now carried out within the late summer season (September) somewhat than the spring or fall (October), partially as a consequence of sea ice adjustments but in addition as a result of bowhead whale numbers are increased than they’ve been in a century.
Kaktovik residents are adapting to these adjustments by shifting the first season of the hunt earlier in the summertime – and sadly, that has had penalties for polar bears in addition to the folks. Bears have discovered by expertise in recent times that it might be price their whereas to remain ashore over the summer season somewhat than keep on the ice because it retreats.
Here’s what Miller and colleagues (2006: 1) needed to say about these adjustments (my daring):
In 1999, the U.S. Fish and Wildlife Service (FWS) started flying aerial surveys alongside the Beaufort Sea shoreline between Cape Halkett and Jago Spit close to Barter Island (Determine 1) through the fall open water interval (September-October) to find out the distribution and abundance of polar bears within the central Beaufort Sea coastal space. Outcomes point out that the bulk (73%) of polar bears noticed in 2000-2004 had been positioned inside 12 km of Barter Island, the place unused parts of bowhead whales (Balaena mysticetus) had been deposited by Kaktovik residents throughout fall whaling.
The inhabitants of Kaktovik was 293 residents in 2000, most of whom are Native (U.S. Census Bureau 2000). Bowhead whale looking has been and continues to be an necessary a part of the native tradition and way of life (Jacobson and Wentworth 1982). Current fall bowhead whale harvests had been first recorded at Kaktovik in 1964; since 1989, two to 4 whales have been harvested yearly (Koski et al. 2005). The bulk (64%) of whales are taken between September 1 and 20 (Koski et al. 2005). Lately, a big development in direction of earlier harvest has occurred, most likely due to improved looking strategies and gear, and maybe additionally as a result of the scale of the bowhead inhabitants is growing, and whales could also be extra quite a few close to Kaktovik early within the looking season (Koski et al. 2005).“
Extra on Kaktovik bears right here (and right here), with quotes from previous tales and hyperlinks to extra footage, and on the standing of SB bears right here.
I’ll add that polar bears are identified to go to Kaktovik and different small communities throughout the coast of Alaska always of yr, not simply in summer season, and nearly the entire bears photographed on shore in Alaska in recent times have been fats and wholesome. The photograph beneath exhibits a fats grownup feminine and her two fats cubs trying out the whale bone pile at Kaktovik in April 2016, a time of yr when bears are normally on the ocean ice looking seals:
Atwood, T.C., Peacock, E., McKinney, M.A., Lillie, Ok., Wilson, R., Douglas, D.C., and others. 2016. Speedy Environmental Change Drives Elevated Land Use by an Arctic Marine Predator. PLoS ONE 11(6): e0155932. doi:10.1371/journal.pone.0155932 pdf right here.
Herreman, J. and Peacock, E. 2013. Polar bear use of a persistent meals subsidy: Insights from non-invasive genetic sampling in Alaska. Ursus 24(2):148–163. Pdf right here.
Miller, S., Schliebe, S. and Proffitt, Ok. 2006. Demographics and Conduct of Polar Bears Feeding on Bowhead Whale Carcasses at Barter and Cross Islands, Alaska, 2002-2004. Alaska Outer Continental Shelf (OCS) Research MMS 2006-14, US Dept. of the Inside, Minerals Administration Service, Anchorage. Pdf right here.
Miller, S., Wilder, J. and Wilson, R.R. 2015. Polar bear–grizzly bear interactions through the autumn open-water interval in Alaska. Journal of Mammalogy http://jmammal.oxfordjournals.org/content material/early/2015/09/10/jmammal.gyv140
Rode, Ok.D., Douglas, D., Durner, G., Derocher, A.E., Thiemann, G.W., and Budge, S. 2013. Variation within the response of an Arctic high predator experiencing habitat loss: feeding and reproductive ecology of two polar bear populations. Oral presentation by Karyn Rode, 28th Lowell Wakefield Fisheries Symposium, March 26-29. Anchorage, AK. Summary beneath, pdf right here.
Rode, Ok.D., Regehr, E.V., Douglas, D., Durner, G., Derocher, A.E., Thiemann, G.W., and Budge, S. 2014. Variation within the response of an Arctic high predator experiencing habitat loss: feeding and reproductive ecology of two polar bear populations. World Change Biology 20(1):76-88. http://onlinelibrary.wiley.com/doi/10.1111/gcb.12339/summary
Rode, Ok. and Regehr, E.V. 2010. Polar bear analysis within the Chukchi and Bering Seas: A synopsis of 2010 area work. Unpublished report to the US Fish and Wildlife Service, Division of the Inside, Anchorage. pdf right here.
Whiteman, J.P., Harlow, H.J., Durner, G.M., Anderson-Sprecher, Albeke, S.E., Regehr, E.V., Amstrup, S.C., and Ben-David, M. 2015. Summer time declines in exercise and physique temperature provide polar bears restricted power financial savings. Science 349 (6245):295-298. Supplemental Materials right here. Summary right here.