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Bumblebees Being Crushed By Climate Change
sciencehabit writes: As the climate changes, plants and animals are on the move. So far, many are redistributing in a similar pattern: As habitat that was once too cold warms up, species are expanding their ranges toward the poles, whereas boundaries closer to the equator have remained more static. Bumblebees, however, appear to be a disturbing exception, according to a new study (abstract) . A comprehensive look at dozens of species finds that many North American and European bumblebees are failing to "track" warming by colonizing new habitats north of their historic range. Simultaneously, they are disappearing from the southern portions of their range.
I think that was the rough idea behind creating Africanized honeybees (killer bees). Not so much because of climate change, but just to be able to make honey in the tropics. And it worked, if you ignore the behavioral changes.
You do realize that bumblebees are not the same as honeybees, right?
I thought bumblebees are everywhere except maybe the desert?
Bombus sonorus -- the Sonoran Bumblebee -- is a common North American desert species.
To answer your question every critter has it's range. Even you do. Visited Antarctica recently? Or Mars?
If you were a bumblebee you'd have a range of about a quarter of a kilometer from your nest. In rare instances you might go as far as 800m distant. And therein you can see why climate change poses an adaptation challenge to bumblebees.
Bumblebee colonies die every winter. The old queen perishes and the new queens hibernate until the spring then disperse to a new nest site. So you can see that the species can only relocate northward at a fraction of a kilometer per year -- although it may have better luck moving vertically -- to higher altitudes where a convenient mountain is handy.
Species that adapt well to climate change either have individuals with large ranges, or they hitch a ride on critters that travel long distance. For example mosquito species have lifetime ranges on the order of 2-3 km, but the Asian Tiger Mosquito (Aedes albopictus), which breeds in small containers of water, usually spends its life within 100m or so of where it hatches. The Tiger Mosquito species was introduced to the US at Houston in 1985 and fifteen years later it was found all over the United States. How is this possible if an individual lives its entire life within a 100m radius of its hatching place? I went to a presentation at CDC Fort Collins where their arthropod borne disease doyen plotted out the spread of Ae albopictus and showed it followed the route of the US Interstate Highway system. Eggs and pregnant individuals hitched a ride. That's because cars and trucks provide things that mosquitoes are attracted to: people to bite and tiny pools of water trapped in spare tires or crevices of the machine for egg-laying. Note that Ae albopictus larvae are known to arrive in the US in a shipments of that "lucky bamboo" you can buy in Chinatown; those stalks hold maybe 20-30 ml of water. It takes a "container" with only a tablespoon or two of water to transport viable larvae.
Now back to bumblebees. Because bumblebee colonies are small (typically 50 individuals to 50,000 for honeybees) and temporary, bumblebees don't stockpile honey. So unlike honeybees humans have no reason to transport them deliberately. Likewise cars and trucks aren't attractive to bumblebees so it's rare that a new queen will get an accidental ride north with a human. So bumblebees are poorly adapted to a rapidly changing climate.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Christ, it's like the 5th paragraph in: "One clue to the importance of climate: Bumblebee ranges began shrinking 'even before the neonicotinoid pesticides came into play in the 1980s,' says ecologist and coauthor Alana Pindar, a postdoctoral fellow at the University of Guelph in Canada."
I've learned that they're worthless, so I don't read AC comments anymore.
Since the range migration started happening "even before the neonicotinoid pesticides came into play in the 1980s,” both of your theories seem to not be relevant to this particular article. Especially the wacky cellphone tower tinfoil hat guy.
Please at least try to RTFA next time.
I've learned that they're worthless, so I don't read AC comments anymore.
In fairness, on behalf of all of us who aren't entomologists ... I had no idea of the difference either.
This gives a rundown of what the differences are.
I bet the majority of people don't know they're different things.
Lost at C:>. Found at C.
Just like anything else in the natural world, small changes effect the outliers first. Bee colonies living on the edge, just getting by, die off if there is even a slight drop in survivability.
To answer your question; sometimes a reduction in food supply and sometimes the weather gets just a little too warm for bees already living on the edge of survivability. Either one can cause a colony to fail.
Climate change was first noted in the early 1970's. The change itself has been ongoing and accelerating over the past 500 years or so. So, no the bees' problem does not predate climate change.
Very often, people confuse simple with simplistic. The nuance is lost on most. - Clement Mok
This has been considered. From the article:
"In addition to land-use changes, we investigated whether pesticide use affected shifts in thermal and latitudinal range limits among bumblebees. Spatially detailed, annual pesticide measurements, including neonicotinoid insecticides, were available for the United States after 1991. Neither total pesticide nor neonicotinoid applications there relate to observed shifts in bumblebee speciesâ(TM) historical ranges or thermal limits (table S1). Neonicotinoid effects known from individual and colony levels certainly contribute to pollinator declines and could degrade local pollination services. Neonicotinoid effects on bumblebees have been demonstrated experimentally using field-realistic treatments (20). These locally important effects do not âoescale upâ to explain cross-continental shifts along bumblebee speciesâ(TM) thermal or latitudinal limits. The timing of climate changeâ"related shifts among bumblebee species underscores this observation: Range losses from speciesâ(TM) southern limits and failures to track warming conditions began before widespread use of neonicotinoid pesticides (figs. S2 and S3). "
http://www.sciencemag.org/cont...
No they weren't. As for various assertions about scientists supposedly saying the climate was getting colder, the report on climate change debunks all that. http://nca2014.globalchange.go...
Very often, people confuse simple with simplistic. The nuance is lost on most. - Clement Mok