One of the most important impacts that climate change has on wildlife populations is that it brings extreme weather with intensified temperature fluctuations. A key element of it is that the change is happening at a dramatically fast rate that forces animals to quickly adapt (CBS News 2018). Specifically, in the Galapagos Islands while the dinosaur-like marine iguana’s ancestors previously only lived on land, the species adapted to swimming and feeding in water (CBS News 2018). The iguana is a result of the evolution that has been accelerated by climate change (CBS News 2018). However, not all animals are able to withstand the major highs and lows. Due to the fluctuation, they experience temperature stress as their habitats degrade and are not able to survive (CBS News 2018). That said, climate change impacts wildlife because it forces them to evolve at a rapid rate in order to survive. As a result, the animals we see in the future are going to look different than the ones existing today. Another significant impact is that the shifting climate is forcing some animals to migrate to habitats where they can survive (CBS News 2018). Due to interdependence in the trophic structure, when a single species expands its range, it impacts the others (Krausman and Cain 2013). Consequentially, there will be range contractions by species, such as animals that need snow to survive, that are not able to move (Krausman and Cain 2013). As a result, trophic cascades can occur. Also, the issue of non-native animals entering new habitats is concerning as one addition to a thriving ecosystem can shift predator-prey dynamics to a detrimental degree.
CBS News, 2018. “Adapt or die: Can evolution outrun climate change?” CBS News. May 20th, 2018. Video, 22:19. https://www.cbsnews.com/news/adapt-or-die-cbsn-originals/
Krausman, Paul R. and James W. Cain III, Eds. 2013 Wildlife Management and Conservation: Contemporary Principles and Practices. Wildlife Management and Conservation Series. Johns Hopkins Univerity Press.
Comment by Mattea Tingle:
You did a great job highlighting the importance of understanding how temperatures affect not only populations but also food dynamics. The movement of species outside of their ranges can alter food availability and competition in other areas with other species. The movement of the species due to food shortages or habitat degradation also affects other species and their own migration patterns. The example of snow is very true since here in Wyoming, I have seen how low snowfall alters the timing in which ungulates begin migrations and when bears begin to hibernate.
Thanks for the comment!
Pigeon et al. (2016) explained bear hibernation has evolved as an adaptive strategy to avoid harsh environmental conditions associated with a lack of resources. They did field-based investigations to determine whether males and females selected dens in response to food availability, within-stand characteristics related to concealment cover, or factors affecting the structural stability of dens (Pigeon et al. 2016). They studied den selection for 10 male and 21 female grizzly bears at the home-range scale and within the den vicinity using data collected at 42 den sites, 168 adjacent sites, and 345 random locations within the Rocky Mountains and boreal forest of Alberta, Canada between 2001 and 2012 (Pigeon et al. 2016). Within their autumn home range, male and female grizzly bears selected sites with greater concealment cover, greater canopy cover, and more abundant sweet-vetch compared to availability (Pigeon et al. 2016). They found no difference in the dimensions and characteristics of dens excavated by males and females, nor in the structural stability of dens dug under a mature tree or in open areas, and no selection for a specific type of mineral soil or percentage of boulders and cobbles (Pigeon et al. 2016). That said, the study emphasized the importance of factors significantly altered by climate change such as food abundance and lateral cover.
Pigeon, Karine, Steeve Cote, and Garden Stenhouse. 2016. “Assessing Den Selection and Den Characteristics of Grizzly Bears.” The Journal of Wildlife Management. 80(5): 884-93.