The freezing and thawing patterns in the Arctic have been increasingly affected as a result of global temperatures increasing, resulting in earlier later freezing and earlier thawing. This is forcing phenology changes in many Arctic species. Particularly, there has been a change in migration patterns in many species due to the lack of frozen bodies of water. This can lead to longer, more strenuous, and more dangerous migrations that can result in higher mortality rates. Leblond et al. (2016) tracked the ice thawing and freezing times for bodies of water in the migration path of caribou Rangifer tarandus Northern Quebec from 2007−2014, allowing them to determine if the change in ice melt was affecting the caribou’s phenology. Their hypothesis was that the caribou would travel extra distance in order to avoid swimming or water that was not completely frozen. They assessed four different parts of the migration: previous data for freezing trends, the caribou’s response to the change in freezing trends, fine-scale caribou behavior and phenology, and possible future movement using climate change projections. Continue reading →
Indigenous communities around increasingly finding that their traditional fishing practices clash with new, externally-imposed conservation policies and societal expectations. Finding an appropriate answer to these disagreements is difficult, especially since there are not enough data about most traditional, or even modern, marine fisheries to be able to create accurate scientific models that could help guide potential management strategies. Marsh et al. (2015) investigate the indigenous Dugong harvest in the Torres Straits, an area that spans the ocean space between Papua New Guinea (PNG) and the Northern Australian coast. Based on Marsh et al.’s preliminary research, the harvests here have been taking place for 4,000 to 7,000 years and have been “substantial,” for 400 to 500 years. With concerns about the conservation of ecosystems becoming more prevalent and politically involved, more and more people in Australia and PNG are calling for a ban or for restrictions to Dugong harvests. So far, regulations have already been set in place to limit hunting in certain areas and with certain equipment, but, because of the Australian Native Title Act, the Torres Strait islanders are lawfully allowed to hunt in what is known as their, “sea country,” as long as they follow a few restrictions. Marsh et al. argue that previous studies which stated that dugong harvests are largely unsustainable are actually incomplete due to the absence of good population and hunting data. Marsh et al. estimate that the Dugong harvest is sustainable and suggest that typical conservation methods should not be used to manage the Dugong harvests. Instead, they suggest that until sufficient data is available to use more popular management methods, a cultural reinforcement strategy currently in use, which involves ancient, traditional limitations on when, where, and how many Dugong can be harvested, should be implemented to manage this harvesting activity. These cultural reinforcements, driven by the indigenous communities themselves, must be coupled with detailed hunting reports as well as collaborations between government officials and indigenous leaders to create a more efficiently tailored management system for the dugong harvest. Continue reading →
The great increase of species extinctions due to human-related habitat destruction, pollution, overharvesting and global climate change, often force conservationists to choose which species to help. Usually species that are poor dispersers, with few populations, low reproduction rates, or very specific environmental requirements, reproductive site or feeding habits, are most vulnerable to extinction. Endemic species, limited to a specific habitat, fall under the list of vulnerable species, small changes in their niche, including temperature, can be enough to destabilize the population to the point of extinction. Continue reading →
The American pika, a cousin of rabbits and hares found in the mountains of western North America, may serve as a model organism for examining the effects of global warming on montane species. Pikas tend to live on talus slopes at higher elevations, and as their lower elevation limits are relatively high they may be especially vulnerable to climate change. Having adapted to colder climates pika are susceptible to hyperthermia in the summer, with a lethal upper body temperature occurring at only 3°C above their resting body temperature. During times of high temperature pikas reduce their foraging time to keep their body temperatures low, which also reduces their energy intake. Prolonged periods of high temperature can lead to reduced reproduction and death. Summer temperatures can thus place serious limits on the pika’s distribution. Stewart et al (2015) created a model to assess the potential risk posed to piks and other climate-sensitive mammals by climate change. Their model matched previous findings and predicted high levels of extirpation of pikas in study sites across California, with the size of talus area and summer temperatures being the best predictors of range. Continue reading →
Our newest book, published on May 6, 2015 and available at Amazon.com for $19.95.
The focus of this book is the interactions between energy, ecology, and climate change, as well as a few of the responses of humanity to these interactions. It is not a textbook, but a series of chapters discussing subtopics in which the authors were interested and wished to write about. The basic material is cutting-edge science; technical journal articles published within the last year, selected for their relevance and interest. Each author selected eight or so technical papers representing his or her view of the most interesting current research in the field, and wrote summaries of them in a journalistic style that is free of scientific jargon and understandable by lay readers. This is the sort of science writing that you might encounter in the New York Times, but concentrated in a way intended to give as broad an overview of the chapter topics as possible. None of this research will appear in textbooks for a few years, so there are not many ways that readers without access to a university library can get access to this information.
This book is intended be browsed—choose a chapter topic you like and read the individual sections in any order; each is intended to be largely stand-alone. Reading all of them will give you considerable insight into what climate scientists concerned with energy, ecology, and human effects are up to, and the challenges they face in understanding one of the most disruptive—if not very rapid—event in human history; anthropogenic climate change. The Table of Contents follows: Continue reading →
Rühl et al. (2015) writing in Biological Conservation attempted to determine whether predicted changes in temperature as caused by global warming would be detrimental to the survival of endangered arable weed species, which play an important role in increasing biodiversity. The results of the study were multiple. The authors concluded that endangered arable weed species germinated significantly less than the common arable weed species under increased temperature conditions and preferred lower optimal germination temperatures (24°C ± 3.5) than common arable weed species (31°C ± 0.5). Continue reading →
While the impact of climate change on a variety of animal populations and their ranges has been studies extensively in the past, the study of the impact of warming on tree species also provides useful information for policymaking. A variety of different modeling systems apply different variables and make predictions about tree species distribution in the future as temperatures rise. In this study however, Prasad et al. (2013) combine two different commonly used technologies to overcome the constraint of computation time and allow assessment of colonization potential for oak species. Four oak species were chosen to focus on because they are strongly climate-driven species: black oak, post oak, chestnut oak, and white oak. Using the DISTRIB and SHIFT models together the authors were able to determine the future dominant forest types in the northeastern United States. This study determined that even under optimistic conditions ignoring some influential factors, only a small fraction of suitable oak habitat is likely to be occupied by oaks within 100 years. The authors urge that the information garnered in this study be used to inform assisted migration practices for vulnerable tree species. They additionally call for further studies focusing on how each individual species will adapt to increases in temperature. Continue reading →
The value of biodiversity for the resilience of ecological systems has become common knowledge in ecology spheres. Moreover, the affects of humans on the diversity of many ecosystems around the world have been proven previously. This study connects these two pieces of knowledge in stating that the combination of diversity loss caused by human activities and environmental change increase the risk for sudden ecosystem collapse. MacDougall et al. (2013) demonstrated this connection in a degraded but species-rich grassland that was subject to fire suppression techniques as well as invasion by non-native species. The authors conclude that human disturbance created a negative relationship between diversity and function but that the elimination of the buffering effects of high species diversity has led to a vulnerability to sudden environmental change. The findings of this study can be applied more generally to many different ecosystems because of the prevalent combination of long-term land management and species loss. This study relates to climate change because as global temperatures cause fires to increase in occurrence and severity, trophic collapse because of human-caused diversity loss may also increase. Continue reading →
In the nineteenth century Arctic tundra of Finnmark, Norway, the Arctic fox population declined to near extinction and have been recovering minimally despite strict protection. Hamel et al. (2013) investigated potential factors involved in suppressing healthy recolonization of prior territories, including encroaching red fox populations and variation in prey availability. By baiting and periodically photographing the area, the authors found red foxes to be the most important influence on the Arctic fox population in northeast Norway. Not only are red foxes more comfortable in the warming temperatures of the tundra, but there has also been a significant reduction in fox hunting, allowing the red fox population to flourish. Rodent population fluctuations were first documented alongside fox populations as a limiting factor of population growth; however, they had fewer effects than either land cover changes or red fox infiltration. Continue reading →
While it has become fairly well known that global warming will cause plant and animal species to migrate toward cooler areas or cause range loses, until now it has been unclear whether this will also be true for microorganisms. Microorganisms play a key role in soil fertility and erodibility making this study relevant both for future agricultural endeavors as well as future efforts relating to ecological protection. Garcia-Pitchel et al. (2013) conducted continental-scale compositional surveys of soil crust microbial communities in the arid regions of North America. The results from these surveys imply that temperature caused latitudinal replacement between two key topsoil cyanobacteria. The cyanobacteria Microcoleus vaginatus behaved more psychrotolerant and less thermotolerant while M. steenstrupii behaved more thermotolerant. These results imply that the later may replace the former as temperature increases globally. Further studies are required to fully understand the impact of this microbial replacement. Continue reading →