Climate Change Alters Cast of Winter Birds

Author: Terry Devitt, University of Wisconsin
Website: Science Daily
Link: http://www.sciencedaily.com/releases/2014/10/141017183444.htm

Summary:
         
      According to University of Wisconsin-Madison wildlife biologists Benjamin Zuckerberg and Karine Princé, birds that are typically found in more southerly regions of the planet have been gradually pushing north over the past two decades, restructuring the communities of birds that spend their winters in the more northern latitudes of Earth.  According to the wildlife biologists, birds such as cardinals, chipping sparrows, Carolina wrens, and other feathered species more adapted to warmer climates have greatly expanded the ranges of their winter migrations in a warmer world, a change that may have untold consequences for ecosystems in North America. According to research, these types of birds were rare in the more northern regions of North America fifty years ago. A shifting winter climate has allowed for smaller, more southerly distributed bird species to colonize new regions and create more unique groups of winter birds throughout North America, which will continue to occur in years to come if the rate of climate change on Earth remains the same. The changes in the mix of overwintering bird species are occurring due to recent winters with less snow, more varied and intense natural weather events, and a generally shorter overall snow season. Climate models based on data collected in past years predict even warmer temperatures occurring over the next 100 years, with seasonal climate effects being the most pronounced in northern regions of the world. It is noted in the article that "removing or introducing even a single species can have a cascade of ecological consequences, many of them unknown."

Connection:
         
      This article connects to our unit on ecosystems and climate change, factors that limit a population, and our exploration in discovery science. This article revolves around the effects of climate change, which we touched highly upon in our unit as it invokes biotic and abiotic changes over time in an ecosystem. During our class, we discussed how limiting factors prevent a J-shaped growth curve in a species, one of these factors including living space. However, in the article, it is stated that how this limiting factor of living space is relaxed due to climate change is causing the gradual expansion up north by making northerly areas of North America more suitable for these species of birds. The scientists involved in this experiment use models to present the data collected by means of discovery science from past years in order to be able to analyze the effects of climate change on the bearings of winter birds.


- Jessica Luo