Ecological Effects Of Climate Change Research Articles

Ecological effects of longline fishing and climate change on the pelagic ecosystem off eastern Australia

Pelagic longline fisheries target (or catch incidently) large apex predators in the open ocean (e.g. tunas, billfish and sharks) and have the potential to disrupt the ecosystem functionality if these predators exert strong top–down control. In contrast, warming of oceans from climate change may increase bottom–up effects from increases in primary productivity. An ecosystem model of a large pelagic ecosystem off eastern Australia was constructed to explore the potential ecological effects of climate change and longlining by Australia’s Eastern Tuna and Billfish Fishery. The model reproduced historic biomass and fishery catch trends from 1952 to 2006 for seven functional groups. Simulated changes in fishing effort and fishing mortality rate on individual target species from 2008 to 2018 resulted in only modest (<20%) changes in the biomass of target species and their direct predators or competitors. A simulated increase in phytoplankton biomass due to climate change resulted in only small increases (<11%) in the biomass of all groups. However, climate-related changes to the biomass of micronekton fish (−20%) and cephalopods (+50%) resulted in trophic cascades. Our results suggest there may be ecological redundancy among high trophic level predators since they share a diverse suite of prey and collectively only represent <1% of the total system biomass. In contrast, micronekton fishes and cephalopods have high biomasses and high production and consumption rates and are important as both prey and predators. They appear to exert ‘wasp–waist’ control of the ecosystem rather than top–down or bottom–up processes reported to drive other pelagic systems.

Coupling low and high trophic levels models: Towards a pathways-orientated approach for end-to-end models

Existing models of marine ecosystems address specific issues related to the bottom-up forcing of production or to the top-down effects of fishing on a limited range of the trophic spectrum. Very few existing models explicitly incorporate the dynamics from one end of the ecosystem to the other and thus allowing the exploration of interplay between exploitation and climate effects. The shift to an ecosystem approach to fisheries and concerns about the ecological effects of climate change require the assemblage of knowledge assembled from the respective marine disciplines with the view to build end-to-end models of marine ecosystems. Here, with a focus on plankton and fish models, we present some issues and recommendations for the integration of models between trophic levels (vertical integration) and within functional groups (horizontal integration within trophic levels). At present, vertical coupling of plankton and fish models is mainly realized through predation processes, generally represented as a functional response. In the absence of empirical evidence and quantification, the choice of the functional response term is often made by default, and is reduced to a parameterization problem. A strategy is proposed to overcome this arbitrary choice. In addition to the vertical coupling of trophic models, the structure of end-to-end models incorporates biodiversity via horizontal integration of trophic levels. For guiding the selection of key components to be included in end-to-end models, the idea that marine food webs are structured as alternative trophic pathways is highlighted and related to observed dynamics. We suggest that an important early step in model development is the identification of major trophic pathways and bottlenecks in an ecosystem using a historical perspective.

Linking Thermal Tolerances and Biogeography:Mytilus edulis(L.) at its Southern Limit on the East Coast of the United States

Temperature is a major factor contributing to the latitudinal distribution of species. In the Northern Hemisphere, a species is likely to be living very close to its upper thermal tolerance limits at the southern limit of its biogeographic range. With global warming, this southern limit is expected to shift poleward. Moreover, intertidal ecosystems are expected to be especially strongly affected, mostly due to their large daily and seasonal variations in temperature and exposure. Hence, these are model systems in which to conduct experiments examining the ecological effects of climate change. In this study we determined the upper lethal thermal limits, for both air and water, of the blue mussel Mytilus edulis via laboratory experiments. Tolerances vary seasonally, with a difference between media of 0.7 degrees C in June and 4.8 degrees C in November, as well as a decrease with multiple exposures. Measured lethal limits were then compared to field measurements of environmental temperature and concurrent measurements of mortality rates. Field results indicate that mortality in the intertidal occurs at rates expected from laboratory responses to elevated temperature. Hindcasts, retrospective analyses of historical data, indicate that high rates of mortality have shifted 51 and 42 days earlier in Beaufort, North Carolina, and Oregon Inlet, North Carolina, respectively, between 1956 and 2007. The combined data suggest that the historical southern limit of M. edulis near Cape Hatteras, North Carolina, is indeed the result of intolerance to high temperature, and that this range edge is shifting poleward in a manner indicative of global warming.

Reconciling the influence of global climate phenomena on macrofaunal temporal dynamics at a variety of spatial scales

AbstractDetermining the relative importance of environmental forces on population dynamics is a fundamental question for ecologists. Growing concern over the ecological effects of climate change emphasizes the importance of defining whether broad‐scale environmental forces uniformly act upon local populations (hierarchy theory) or cross‐scale interactions influence local responses (multiscale theory). This study analyses 13 years of data on species abundances at six sites within a large harbour to determine the effect of the El Niño Southern Oscillation (ENSO). Environmental variables both directly and indirectly related to ENSO were observed to be important predictors of the temporal dynamics of abundance in many species, but the observed effects were not consistent across sites or species. While nearly all species were affected by large temporal and spatial scale variability, smaller temporal scale, location‐specific environmental variables (such as wind‐generated wave exposure and turbidity) were also generally important, increasing the variability explained by our models by up to 25%. As with many other broad‐scale variables, generality of response to ENSO is affected by interactions across time and space with smaller scale heterogeneity. This study therefore suggests that the degree of interaction between broad‐scale climatic factors, such as ENSO, with smaller scale variability, will determine the consistency of responses over large spatial scales, and control our ability to predict effects of climate change on coastal and estuarine communities.

Warming strengthens an herbivore-plant interaction.

Temperature has strong, predictable effects on metabolism. Through this mechanism, environmental temperature affects individuals and populations of poikilotherms by determining rates of resource use, growth, reproduction, and mortality. Predictable variation in metabolic processes such as growth and reproduction could affect the strength of species interactions, but the community-level consequences of metabolic temperature dependence are virtually unexplored. I experimentally tested the hypothesis that plant-herbivore interaction strength increases with temperature using a common species of marine macroalga (Sargassum filipendula) and the grazing amphipod Ampithoe longimana. Increasing temperature increased per capita interaction strength in two independent experiments and reversed a positive effect of temperature on plant growth. Temperature did not alter palatability of plant tissue to herbivores or average herbivore feeding rate. A predictable effect of temperature on herbivore-plant interaction strength could provide key information toward understanding local food web responses to changing temperatures at different spatial and temporal scales. Efforts to extend the effects of physiological mechanisms to larger scale patterns, including projections of the ecological effects of climate change, must be expanded to include the effects of changing conditions on trophic interactions.

Exporting the ecological effects of climate change

Global anthropogenic climate change is contributing to the considerable economic imbalance between rich and poor nations. The changing climate will inevitably influence natural resources, but it is the poorest countries—where humans rely most directly on natural systems for their livelihoods—that are expected to experience the greatest changes. Accordingly, the resources, economies and societies of these nations are likely to be most severely affected, despite the fact that they are least able to cope with—and are least responsible for—climate change itself. Here, we analyse which countries and regions will suffer the most severe changes to their natural ecosystems and biodiversity, and how the responsibility for those changes is distributed across the world. > The changing climate will inevitably influence natural resources, but it is the poorest countries […] that are expected to experience the greatest changes On a broad scale, geographic variations in temperature, rainfall and seasonality determine ecosystem productivity and species diversity. Ecosystems therefore respond to changes in temperature and precipitation, which inevitably have an impact on biodiversity. Recent shifts in the distributions of various species towards the poles and to higher altitudes (Parmesan & Yohe, 2003; Root et al , 2003; Walther et al , 2005; Wilson et al , 2005; Franco et al , 2006; Hickling et al , 2006), and the extinction of more than 1% of all amphibian species (Pounds et al , 2006), indicate that climate change is already having a major impact on biodiversity. Climatic changes are also expected to alter the distributions of most types of vegetation (Cramer et al , 2001; Scholtze et al , 2006) and there is already evidence of a shift from deciduous woodland to evergreen forest in part of southern Europe (Walther et al , 2002). Such changes will have implications both for biodiversity (Malcolm et al , 2006) and for the humans …

Keeping up with a warming world; assessing the rate of adaptation to climate change

The pivotal question in the debate on the ecological effects of climate change is whether species will be able to adapt fast enough to keep up with their changing environment. If we establish the maximal rate of adaptation, this will set an upper limit to the rate at which temperatures can increase without loss of biodiversity. The rate of adaptation will primarily be set by the rate of microevolution since (i) phenotypic plasticity alone is not sufficient as reaction norms will no longer be adaptive and hence microevolution on the reaction norm is needed, (ii) learning will be favourable to the individual but cannot be passed on to the next generations, (iii) maternal effects may play a role but, as with other forms of phenotypic plasticity, the response of offspring to the maternal cues will no longer be adaptive in a changing environment, and (iv) adaptation via immigration of individuals with genotypes adapted to warmer environments also involves microevolution as these genotypes are better adapted in terms of temperature, but not in terms of, for instance, photoperiod.Long-term studies on wild populations with individually known animals play an essential role in detecting and understanding the temporal trends in life-history traits, and to estimate the heritability of, and selection pressures on, life-history traits. However, additional measurements on other trophic levels and on the mechanisms underlying phenotypic plasticity are needed to predict the rate of microevolution, especially under changing conditions. Using this knowledge on heritability of, and selection on, life-history traits, in combination with climate scenarios, we will be able to predict the rate of adaptation for different climate scenarios. The final step is to use ecoevolutionary dynamical models to make the link to population viability and from there to biodiversity loss for those scenarios where the rate of adaptation is insufficient.

Top predators provide insurance against climate change

Recent research by Wilmers et al. shows that top predators might buffer some of the ecological effects of climate change. Top predators can regulate the structure of entire communities and dampen their variability; however, in their absence, prey populations are likely to fluctuate greatly owing to bottom-up factors. Restoring top predators to their natural environment could provide insurance against undesired effects of climate change on ecological communities.

Constraints to projecting the effects of climate change on mammals

CR Climate Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials CR 32:151-158 (2006) - doi:10.3354/cr032151 Constraints to projecting the effects of climate change on mammals D. Berteaux1,*, M. M. Humphries2, C. J. Krebs3, M. Lima4, A. G. McAdam5, N. Pettorelli6, D. Réale7, T. Saitoh8, E. Tkadlec9, R. B. Weladji6, N. Chr. Stenseth10 1Canada Research Chair in Conservation of Northern Ecosystems and Centre d’études nordiques, Université du Québec à Rimouski, 300 allée des Ursulines, Rimouski, Québec G5L 381, Canada 2Department of Natural Resource Sciences, Macdonald Campus, McGill University, 21-111 Lakeshore Road, Ste-Anne-de-Bellevue, Québec H9X 3V9, Canada 3Department of Zoology, University of British Columbia, 6270 University Boulevard, Vancouver, British Columbia V6T 1Z4, Canada 4Center for Advanced Studies in Ecology and Biodiversity, Pontificia Universidad Catolica de Chile, Casilla 114-D, Santiago CP 6513677, Chile 5Department of Fisheries & Wildlife, Department of Zoology, 13 Natural Resources Building, Michigan State University, East Lansing, Michigan 48824, USA 6Département de Biologie, Université Laval, Québec G1K 7P4, Canada 7Canada Research Chair in Behavioural Ecology, Université du Québec à Montréal, CP 8888-succursalle centre-ville, Montréal, Québec H3C 3P8, Canada 8Field Science Center, Hokkaido University, North 11, West 10, Sapporo 060-0811, Japan 9Palacky University, Department of Ecology and Environmental Sciences, Tr. Svobody 26, 771 46 Olomouc and Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, 675 02 Studenec, Czech Republic 10Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biology, University of Oslo, PO Box 1066, Blindern, 0316 Oslo, Norway *Email: dominique_berteaux@uqar.qc.ca ABSTRACT: Ecologists are under pressure to anticipate the ecological effects of climate change. Therefore many ecological publications (and most grant proposals) related to climate claim relevance to the projection of future climate change effects. Yet the steps leading from ecological description and understanding to reliable projection are rarely explicit. A good understanding of the factors which allow the ecological effects of climate change to be effectively anticipated is critical to both the quality of basic science and its application to public policy. We used research performed on mammals to explore scientific approaches to anticipation of climate change effects. We distinguished forecasting models based on correlations from predictive models based on cause-effect relationships. These categories represent extremes along a continuous gradient between pattern description and causal understanding. We suggest that the constraints to our capacity to anticipate fall into 6 broad categories rooted in the development and application of forecasting and predictive models. These categories help to identify the conditions that allow or prevent projection of the effects of climate change on ecosystems. This approach should also help to identify which research avenues will likely be most fruitful. KEY WORDS: Cause-effect relationships · Climate change · Ecology · Forecasting · Mammals · Models · Prediction · Scientific projection · Time series Full text in pdf format PreviousExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in CR Vol. 32, No. 2. Online publication date: October 13, 2006 Print ISSN: 0936-577X; Online ISSN: 1616-1572 Copyright © 2006 Inter-Research.

East Atlantic teleconnection pattern and the decline of a common arctiid moth

AbstractTeleconnection patterns are large‐scale atmospheric circulation systems and variation in them is often associated with impacts on climate and weather over broad areas. Arctia caja L. is a well‐known, widespread and charismatic tiger moth. In recent decades, the abundance of A. caja in UK has fallen abruptly. The annual abundance of A. caja in UK is known to be affected adversely by wet winter weather and warm spring temperatures. We examined A. caja population dynamics from 1968 to 1999 for weather and climatological effects. Population growth rate displayed endogenous effects of abundance in the previous two seasons. Accounting for this, growth rate in the present season was still affected significantly by winter precipitation and spring temperature. Annual abundance of A. caja was inversely related to winter East Atlantic teleconnection pattern (winter EA index) and annual population growth rate was inversely related to winter EA in the present and previous two seasons. An index of the North Atlantic Oscillation (NAO), commonly used as an indicator of winter climate in northern Europe, did not show a significant relationship with growth rate. We noted, for the first time, that the winter EA index has increased steadily over the past five decades. The model presented here therefore implies a further decline of A. caja population growth rates and abundance in the future. This is the first demonstration of a relationship between EA and population dynamics and indicates the EA and other lesser‐known teleconnection patterns may prove useful in modeling the ecological effects of climate change.

Climate Change in the Sub-Antarctic: An Illustration from Marion Island

The oceanic climate of Marion Island (sub-Antarctic; 47° S, 38° E) is exceptionally thermally-stable, yet between 1969 and 1999 annual mean surface air temperature at the island increased by 1.2 ° C. Warming has occurred in all months excepting June. Annual precipitation decreased since the mid 1960s, so that the 1990s was the driest of the five decades that precipitation has been measured at the island. All months excepting October have become drier. The interannual variability in annual total sunshine hours was large, and irregular, but a significant proportion of that variability could be ascribed to an average increase of 3.3 hours each year between 1951 and 1999. Hours of sunshine increased for all months in that period. It is argued that the Antarctic region has not taken its rightful place in studies of the biological and ecological effects of climate change and that sub-Antarctic islands, especially, have much to offer in this field. Climatic change will directly affect the indigenous biota sub-Antarctic islands. An even greater threat is that a warmer climate will increase the ease with which the islands can be invaded by alien species and examples are given of how climatic change and invasive organisms influence the biota and ecology of Marion Island.

Searching Museums From Your Desktop

WEB TOOLSWith a few mouse clicks, scientists can now troll the holdings of six museums using a software program called The Species Analyst that was released as a prototype last month on the Web. Expected to expand to 40 institutions or more by year's end, the network linked by The Species Analyst could become a potent way to bring museum and survey data to bear on pressing policy needs, such as tracking the ecological effects of climate change, designing preserves for endangered species, or managing deleterious invading species like the hardwood-chomping Asian longhorn beetle.

Infective hemolymph from forest tent caterpillars diseased by nuclear polyhedrosis virus

Natural and managed ecosystems are undergoing rapid environmental change due to a growing human population and associated increases in industrial and agricultural activity. Global environmental change directly and indirectly impacts insect herbivores and pollinators. In this review, we highlight recent research examining how environmental change factors affect plant chemistry and, in turn, ecological interactions among plants, herbivores, and pollinators. Recent studies reveal the complex nature of understanding global change effects on plant secondary metabolites and plant–insect interactions. Nonetheless, these studies indicate that phytochemistry mediates insect responses to environmental change. Future research on the chemical ecology of plant–insect interactions will provide critical insight into the ecological effects of climate change and other anthropogenic disturbances. We recommend greater attention to investigations examining interactive effects of multiple environmental change factors in addition to chemically mediated plant–pollinator interactions, given limited research in these areas.