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In a warmer Arctic, mosquitoes avoid increased mortality from predators by growing faster.

ABSTRACT: Climate change is altering environmental temperature, a factor that influences ectothermic organisms by controlling rates of physiological processes. Demographic effects of warming, however, are determined by the expression of these physiological effects through predator-prey and other species interactions. Using field observations and controlled experiments, we measured how increasing temperatures in the Arctic affected development rates and mortality rates (from predation) of immature Arctic mosquitoes in western Greenland. We then developed and parametrized a demographic model to evaluate how temperature affects survival of mosquitoes from the immature to the adult stage. Our studies showed that warming increased development rate of immature mosquitoes (Q10 = 2.8) but also increased daily mortality from increased predation rates by a dytiscid beetle (Q10 = 1.2-1.5). Despite increased daily mortality, the model indicated that faster development and fewer days exposed to predators resulted in an increased probability of mosquito survival to the adult stage. Warming also advanced mosquito phenology, bringing mosquitoes into phenological synchrony with caribou. Increases in biting pests will have negative consequences for caribou and their role as a subsistence resource for local communities. Generalizable frameworks that account for multiple effects of temperature are needed to understand how climate change impacts coupled human-natural systems.

SUBMITTER: Culler LE

PROVIDER: S-EPMC4614756 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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In a warmer Arctic, mosquitoes avoid increased mortality from predators by growing faster.

Culler Lauren E LE Ayres Matthew P MP Virginia Ross A RA

Proceedings. Biological sciences 20150901 1815

Climate change is altering environmental temperature, a factor that influences ectothermic organisms by controlling rates of physiological processes. Demographic effects of warming, however, are determined by the expression of these physiological effects through predator-prey and other species interactions. Using field observations and controlled experiments, we measured how increasing temperatures in the Arctic affected development rates and mortality rates (from predation) of immature Arctic m ...[more]

PMID: 26378217

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In a warmer Arctic, mosquitoes avoid increased mortality from predators by growing faster.

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In a warmer Arctic, mosquitoes avoid increased mortality from predators by growing faster.

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