Research shows that as temperatures in the Arctic rise, mosquitoes in the region emerge earlier and grow faster, posing a possible threat to the caribou population they feed on.
In a study published in the journal Proceedings of the Royal Society B: Biological Sciences, researchers predict that the probability of mosquitoes surviving and thriving to become adults increase by over 50 percent if the Arctic experiences a temperature increase of 35.6 degrees Fahrenheit. The results of the study are relevant because the intensity and timing of emergence affects the role of Arctic mosquitoes as pests, pollinators and prey.
The climate-population model it used can be generalized to assess any kind of ecosystem where survival is dependent from sensitivities to changes in the temperature. Arctic region proved it useful because it offered a simple predator-prey relationship that could easily be assessed. In this case, the top predator for arctic mosquitoes is the diving beetle.
Researchers determined the effects of increasing temperatures on the life cycle of Arctic mosquitoes in western Greenland, examining rates of development and death due to predation involving immature mosquitoes. Consequently, they developed a model to evaluate how temperature affects mosquitoes' survival by incorporating different temperature readings, simulating future scenarios - that may be experienced in the region due to climate change.
Warmer temperatures in spring led to Arctic mosquito eggs hatching two weeks earlier, shortening development time between the larval and pupal stages by around 10 percent for every degree that the temperature rises. More of them are eaten by diving beetles. Conclusively, because they are also growing faster, mosquitoes leave the waters shortly which lessened the threat of aquatic predators.
Researchers projected that a two-degree increase in temperature in the region improving chances of survival by 53 percent. The average Arctic temperature has risen to two times the global rate over a century.
Conclusively, as more mosquitoes live well into adulthood, the more they become a threat to the caribou population whose life cycle they are closely synchronized with as the temperatures increase. To sustain reproductive success, female Arctic mosquitoes must feed on blood. With mosquito development coinciding with calving season, female mosquitoes gain access to a large but less mobile herd to feed on.
Such mosquitoes become a threat to caribous due to their faster growth. Because in order for the mosquitoes to survive, their females must feed on blood - of caribous that have a closely synchronized such pests' life cycle. Evidently, the females gain access to the large - but to less, in groups - herd.
"Warming in the Arctic can thus challenge the sustainability of wild caribou and managed reindeer in Fennoscandia," says Lauren Culler, the lead author for the study.
