Search USGS⌕ Search

SEARCH · Search USGS

Results for “Marine Ecology”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources
USGS2003

Ecological criteria for evaluating candidate sites for marine reserves

Several schemes have been developed to help select the locations of marine reserves. All of them combine social, economic, and biological criteria, and few offer any guidance as to how to prioritize among the criteria identified. This can imply that the relative weights given to different criteria are unimportant. Where two sites are of equal value ecologically, then socioeconomic criteria should dominate the choice of which should be protected. However, in many cases, socioeconomic criteria are given equal or greater weight than ecological considerations in the choice of sites. This can lead to selection of reserves with little biological value that fail to meet many of the desired objectives. To avoid such a possibility, we develop a series of criteria that allow preliminary evaluation of candidate sites according to their relative biological values in advance of the application of socioeconomic criteria. We include criteria that, while not strictly biological, have a strong influence on the species present or ecological processes. Our scheme enables sites to be assessed according to their biodiversity, the processes which underpin that diversity, and the processes that support fisheries and provide a spectrum of other services important to people. Criteria that capture biodiversity values include biogeographic representation, habitat representation and heterogeneity, and presence of species or populations of special interest (e.g., threatened species). Criteria that capture sustainability of biodiversity and fishery values include the size of reserves necessary to protect viable habitats, presence of exploitable species, vulnerable life stages, connectivity among reserves, links among ecosystems, and provision of ecosystem services to people. Criteria measuring human and natural threats enable candidate sites to be eliminated from consideration if risks are too great, but also help prioritize among sites where threats can be mitigated by protection. While our criteria can be applied to the design of reserve networks, they also enable choice of single reserves to be made in the context of the attributes of existing protected areas. The overall goal of our scheme is to promote the development of reserve networks that will maintain biodiversity and ecosystem functioning at large scales. The values of ecosystem goods and services for people ultimately depend on meeting this objective.

Ecological Applications↗
USGS1986

Larval settlement into marine soft-sediment systems: Interactions with the meiofauna

The distribution and abundance of organisms exhibiting complex life cycles, like marine invertebrates, reflect ecological processes operating at all stages in the life history. Few studies have yet considered the mortality patterns of larvae and juveniles. To test whether the permanent meiofauna play a role in macrofaunal larval site-selection, and/or if permanent meiofaunal predators or competitors and disturbers are a significant source of mortality for newly settled macrofaunal juveniles, a series of manipulations of meiofauna were performed. Densities of (1) predatory turbellarians alone, and (2) other meiofauna, were increased in small boxes placed on a holding table in a shallow subtidal habitat. Natural settlement into meiofauna manipulations was examined approximately monthly for a year. Other experiments were conducted to examine the relative importance of site-selection and post-settlement mortality and to determine if settlement was density-dependent or density-independent. Densities of spionid, cirratulid, terebellid, capitellid, and maldanid polychaetes, oligochaetes, bivalves, and amphipods were all reduced by high densities of turbellarians, and sometimes by other meiofauna. Turbellarian predation was responsible for significant post-settlement mortality, but spionids, cirratulids, terebellids, and maldanids also appeared to avoid dense turbellarian treatments. Bivalve densities were reduced by high densities of other meiofauna, probably due to their sedimentary disturbance. Syllid polychaete densities were higher in turbellarian treatments, suggesting that they select for areas with high densities of their prey (small turbellarians). The effects of meiofauna on settlement and survival were greatest in spring and summer. The results of these experiments suggest larval settlement patterns and early juvenile survival should be considered in developing general models of life history and community structure for soft-sediment systems.

Journal of Experimental Marine Biology and Ecology↗
USGS2018

Developing Foram-AMBI for biomonitoring in the Mediterranean: Species assignments to ecological categories

Most environmental bio-monitoring methods using the species composition of marine faunas define the Ecological Quality Status of soft bottom ecosystems based on the relative proportions of species assigned to a limited number of ecological categories. In this study we analyse the distribution patterns of benthic foraminifera in the Mediterranean as a function of organic carbon gradients on the basis of 15 publications and assign the individual species to five ecological categories. Our categories (of sensitive, indifferent and 3rd, 2nd and 1st order opportunists) are very similar to the ecological categories commonly used for macrofauna, but show some minor differences. In the 15 analysed publications, we considered the numerical data of 493 taxa, of which 199 could be assigned. In all 79 taxa were classified as sensitive, 60 as indifferent, 46 as 3rd order, 12 as 2nd order and 2 as 1st order opportunists. The remaining 294 taxa are all accessory, and will only marginally contribute to biotic indices based on relative species proportions. In this paper we wanted also to explain the methodology we used for these species assignments, paying particular attention to all complications and problems encountered. We think that the species list proposed here will constitute a highly useful tool for foraminiferal bio-monitoring of soft bottoms in the Mediterranean Sea, which can be used in different ecological indices (Foram-AMBI and similar methods). With additional information becoming available in the next few years, it will be possible to expand the list, and, if necessary, to apply some minor corrections. As a next step, we intend to test this species list using several biotic indices, in a number of independent data sets, as soon as these will become available.

Marine Micropaleontology↗
USGS1983

Habitat Suitability Index Models: Alewife and blueback herring

Alewives and blueback herring are anadromous clupeids found along the Atlantic coast in marine, estuarine, and riverine habitats, depending upon life stage. Both are important commercial species, used fresh or salted for human consumption, and used as crab bait, fish meal (particularly in animal food manufacturing), and fish oil. Alewife and blueback herring are marketed collectively as 'river herring,' a term that will be used for both species in this report. River herring play important ecological roles. In marine, estuarine, and riverine food webs, they occupy a level between zooplankton, their principal food, and piscivores.

FWS/OBS↗
USGS2026

From understanding to action: Integrating new and old methodologies to manage marine infectious disease

Marine diseases can have far-reaching effects on population, community and ecosystem health; however, our ability to track, predict and manage these diseases has, historically, been poor. As a result, the fields of disease ecology and epidemiology have developed at a slower pace for marine than terrestrial systems [ 1 ]. New methodologies, including genomic tools for diagnostics [ 2 , 3 ], transcriptomic tools for measuring host and pathogen responses to infection (e.g. [ 4 , 5 ]), regional oceanic modelling systems that estimate environmental conditions influencing pathogen dispersal and disease progression [ 6 ], artificial intelligence methods for quantifying pathology from images (e.g. [ 7 ]) and advanced disease modelling techniques [ 8 , 9 ] are precipitating a rapid increase in our understanding of marine pathosystems. In 2016, these efforts led to the first special issue of Philosophical Transactions of the Royal Society B ( Marine diseases, volume 371, issue 1689) focused entirely on marine disease ecology and evolution, and in 2020, the first book, Marine disease ecology, was devoted to this topic [ 10 ]. This special issue, focused on marine disease management , is being published a decade after the first Philosophical Transactions special issue on marine diseases. The shift to a management focus reflects an urgent need for management strategies to address high-impact diseases and the rapid methodological advances that have resulted. The papers included in this issue demonstrate the value of combining classical approaches (e.g. routine disease surveillance, reductionistic pathogen challenge trials, rapid throughput diagnostics) with cutting-edge technologies (e.g. high-resolution oceanographic models, Bayesian models, replicated transcriptomic studies) to identify drivers of disease, quantify impacts and suggest management strategies.

Philosophical Transactions of the Royal Society, S↗
USGS2015

Predicting the risk of toxic blooms of golden alga from cell abundance and environmental covariates

Golden alga ( Prymnesium parvum ) is a toxic haptophyte that has caused considerable ecological damage to marine and inland aquatic ecosystems worldwide. Studies focused primarily on laboratory cultures have indicated that toxicity is poorly correlated with the abundance of golden alga cells. This relationship, however, has not been rigorously evaluated in the field where environmental conditions are much different. The ability to predict toxicity using readily measured environmental variables and golden alga abundance would allow managers rapid assessments of ichthyotoxicity potential without laboratory bioassay confirmation, which requires additional resources to accomplish. To assess the potential utility of these relationships, several a priori models relating lethal levels of golden alga ichthyotoxicity to golden alga abundance and environmental covariates were constructed. Model parameters were estimated using archived data from four river basins in Texas and New Mexico (Colorado, Brazos, Red, Pecos). Model predictive ability was quantified using cross-validation, sensitivity, and specificity, and the relative ranking of environmental covariate models was determined by Akaike Information Criterion values and Akaike weights. Overall, abundance was a generally good predictor of ichthyotoxicity as cross validation of golden alga abundance-only models ranged from ∼ 80% to ∼ 90% (leave-one-out cross-validation). Environmental covariates improved predictions, especially the ability to predict lethally toxic events (i.e., increased sensitivity), and top-ranked environmental covariate models differed among the four basins. These associations may be useful for monitoring as well as understanding the abiotic factors that influence toxicity during blooms.

New Mexico, Texas↗
USGS2007

Just Add Water and the Colorado River Still Reaches the Sea

A recent article in Environmental Management by All argued that flood flows in North America’s Colorado River do not reach the Gulf of California because they are captured and evaporated in Laguna Salada, a below sea-level lakebed near the mouth of the river. We refute this hypothesis by showing that (1) due to its limited area, the Laguna Salada could have evaporated less than 10% of the flood flows that have occurred since 1989; (2) low flow volumes preferentially flow to the Gulf rather than Laguna Salada; (3) All’s method for detecting water surface area in the Laguna Salada appears to be flawed because Landsat Thematic Mapper images of the lakebed show it to be dry when All’s analyses said it was flooded; (4) direct measurements of salinity at the mouth of the river and in the Upper Gulf of California during flood flows in 1993 and 1998 confirm that flood waters reach the sea; and (5) stable oxygen isotope signatures in clam shells and fish otoliths recorded the dilution of seawater with fresh water during the 1993 and 1998 flows. Furthermore, All’s conclusion that freshwater flows do not benefit the ecology of the marine zone is incorrect because the peer-reviewed literature shows that postlarval larval shrimp populations increase during floods, and the subsequent year’s shrimp harvest increases. Furthermore, freshwater flows increase the nursery area for Gulf corvina ( Cynoscion othonopterus ), an important commercial fish that requires estuarine habitats with salinities in the range of 26–38‰ during its natal stages. Although flood flows are now much diminished compared to the pre-dam era, they are still important to the remnant wetland and riparian habitats of the Colorado River delta and to organisms in the intertidal and marine zone. Only a small fraction of the flood flows are evaporated in Laguna Salada.

Colorado River↗
USGS2014

Relaxed selection causes microevolution of seawater osmoregulation and gene expression in landlocked Alewives

Ecological transitions from marine to freshwater environments have been important in the creation of diversity among fishes. Evolutionary changes associated with these transitions likely involve modifications of osmoregulatory function. In particular, relaxed selection on hypo-osmoregulation should strongly affect animals that transition into novel freshwater environments. We used populations of the Alewife ( Alosa pseudoharengus ) to study evolutionary shifts in hypo-osmoregulatory capacity and ion regulation associated with freshwater transitions. Alewives are ancestrally anadromous, but multiple populations in Connecticut have been independently restricted to freshwater lakes; these landlocked populations complete their entire life cycle in freshwater. Juvenile landlocked and anadromous Alewives were exposed to three salinities (1, 20 and 30 ppt) in small enclosures within the lake. We detected strong differentiation between life history forms: landlocked Alewives exhibited reduced seawater tolerance and hypo-osmoregulatory performance compared to anadromous Alewives. Furthermore, gill Na + /K + -ATPase activity and transcription of genes for seawater osmoregulation (NKCC—Na + /K + /2Cl − cotransporter and CFTR—cystic fibrosis transmembrane conductance regulator) exhibited reduced responsiveness to seawater challenge. Our study demonstrates that adaptations of marine-derived species to completely freshwater life cycles involve partial loss of seawater osmoregulatory performance mediated through changes to ion regulation in the gill.

Connecticut↗
USGS2026

An Antarctic ecosystem value index to quantify ecological value across trophic levels and over time

The Southern Ocean around Antarctica is one of the fastest changing regions on the planet and an emerging resource frontier for fisheries. Here, we present the Antarctic Ecosystem Value Index created by merging ecosystem information across food web trophic levels, from phytoplankton to fish and penguins, to quantify the ecological value of marine areas around the Antarctic continent. We find that coastal polynyas - areas of reduced sea-ice - have Index values 31–72% higher than surrounding areas, suggesting that these areas are biologically valuable hot spots for a number of ice-dependent Antarctic Species. Using output from an Earth system model to generate future projections of the Index, we find that high-value locations, often within polynyas, are likely to continue to be valuable throughout the 21st century despite environmental changes. The Antarctic Ecosystem Value Index indicates that penguins lose importance as their habitat becomes increasingly unsuitable, so protecting high-value habitat areas may be critical for these species. This study also shows that while many high-value Index areas are within existing or proposed Marine Protected Areas, there are several opportunities for adopting additional protection, particularly in East Antarctica and the Amundsen Sea.

Nature Communications↗
USGS2018

Effect of climate change on disease spread in wildlife

A growing body of evidence indicates that climate change alone, or acting synergistically with current anthropogenic threats, is affecting the health of wild populations of aquatic and terrestrial wildlife. Measurable by-products of climate change include elevated atmospheric concentrations of greenhouse gases, higher average global temperatures; variations in global precipitation patterns, rising and warming oceans, altered hydrographs of rivers, and increased mid-continental drying during summer. These consequences affect the terrestrial environment through shifts in phenology, vegetation cover, and fire regimes. Warmer ocean temperatures, increased acidification, rise in sea levels, and reduction in sea ice cover are also leading to widespread ecological changes in marine systems. Wildlife populations face a variety of climate-related pressures, such as changes in animal distribution or density, limitation of food resources, and alteration to critical habitats. The increased potential for emergence and resurgence of diseases that are responsive to environmental conditions also has implications for wildlife populations. Shifts in temperature or other climatic factors may directly affect the incidence of disease in wildlife by altering host-pathogen interactions, promoting vector populations or allowing new ranges for vectors, or reducing development times for parasites. A number of examples from both field and laboratory studies have demonstrated a clear link between warming environments and disease spread. Many climate-related environmental changes also influence wildlife health indirectly. For example, increasing temperatures, in combination with shifts in rainfall and humidity, may aggravate current trends for water resource limitation and habitat degradation or destruction and lead to increased crowding of animal populations, thereby promoting transmission opportunities of pathogens within populations or across species. Although it may be difficult to disentangle the influences of other anthropogenic changes from the direct effects of warming, some ecosystems provide especially useful models for studying climate-related disease spread in wildlife. For example, the effects of climate change on parasite dynamics may be easily observed in the Arctic, where environmental changes are occurring rapidly, anthropogenic influences are relatively limited, and biodiversity is generally low. Marine ecosystems are also undergoing rapid rates of change and may be vulnerable to a variety of natural and anthropogenic perturbations. Although many factors affect the health of organisms in ocean environments, temperature has been clearly linked to an increase in disease prevalence among sessile organisms such as corals. In this chapter, we discuss observed and predicted changes to wildlife health resulting from climate change. Our review will not include all aspects of wildlife health, but will instead focus on established or suspected links between climate drivers and disease spread and discuss examples from the current literature. Here, we define disease spread to include: 1) change in geographical or altitudinal distribution of pathogens, parasites, and vectors and the diseases they cause; 2) change in prevalence or severity of disease; and 3) emergence of novel diseases. Additionally, because wildlife species serve as reservoirs for zoonotic diseases that affect both animals and humans, we include select examples of the effect of climate change on the capacity of wildlife to harbor and spread these disease agents.

Book chapter↗
USGS2003

Inventory of marine and estuarine fishes in southeast and central Alaska National Parks

As part of a national inventory program funded by the National Park Service, we conducted an inventory of marine and estuarine fishes in Glacier Bay National Park and Preserve, Wrangell-St. Elias National Park and Preserve, Sitka National Historical Park, and Klondike Gold Rush National Historical Park in 2001 and 2002. In addition, marine fish data from a previous project that focused on forage fishes and marine predators during 1999 and 2000 in Glacier Bay proper were compiled for this study. Sampling was conducted with modified herring and Isaacs-Kidd midwater trawls, a plumb staff beam trawl, and beach seines. Species lists of relative abundance were generated for nearshore fishes in all parks, and for demersal and pelagic fishes in Glacier Bay National Park and Preserve and Wrangell-St. Elias National Park and Preserve. With a total sampling effort of 531 sets, we captured 100 species in Glacier Bay National Park and Preserve, 31 species in Wrangell-St. Elias National Park and Preserve, 23 species in Sitka National Historical Park, and 11 species in Klondike Gold Rush National Historical Park. We estimated that between 59 and 85 percent of the total marine fish species present were sampled by us in the various habitat-park units. We also combined these data with historical records and prepared an annotated species list of 160 marine and estuarine fishes known to occur in Glacier Bay National Park and Preserve. Shannon-Wiener diversity index and catch per unit effort were used to assess the effects of depth and latitude (distance from tidewater glaciers) on marine fish community ecology in Glacier Bay proper. Our findings suggest that demersal fishes are more abundant and diverse with increased distance from tidewater glaciers, and that pelagic fishes sampled deeper than 50 m are more abundant in areas closer to tidewater glaciers.

Alaska↗
USGS2008

Coast salish and U.S. Geological Survey: Tribal journey water quality project

The ancestral waters of the Coast Salish People, the Salish Sea, comprise a large inland sea contained within both United States (Puget Sound) and Canadian (Georgia Strait) territory. The Salish Sea is home to more than 220 species of fish, 29 species of marine mammals, more than 40 species of commercial and recreationally harvested invertebrates, and numerous resident and migratory bird species (Washington Sea Grant Program, 2000). Unfortunately, at least 60 of these marine based species are listed as threatened, endangered or of concern (Fraser and others, 2006), many of which sustained Coast Salish for millennia and are of essential cultural importance. The cumulative impacts of human activities and climate change are deteriorating coastal ecosystems and accelerating the loss of ecologically and culturally important marine resources. Watershed modifications, coastal development and industrial activities are altering river and tidal flow, sediment transport, and nutrient delivery all across the region, leading to the break down of ecosystem functions and decreasing biodiversity, thus changing the face of the Salish Sea. A cooperative trans-boundary partnership between the U.S. Environmental Protection Agency (USEPA) and the Government of Canada has identified Salish Sea indicators of health. Several of these indicators have been noted as having degrading quality including urbanization and forest change, river, stream, and lake quality, marine species at risk, toxics in harbor seals, and marine water quality conditions (USEPA, 2008). The functioning of the Salish Sea ecosystem is increasingly threatened by ever more frequent observations and expanding zones of anoxia. The complexities of monitoring, protecting, and restoring such a large and diverse geographical area are exacerbated by a political border. The Coast Salish Peoples and U.S. Geological Survey (USGS) have commenced on a partnership to examine water quality throughout the Georgia Straits and Puget Sound, blending tradition and science, in response to this deterioration of coastal environments and loss of essential habitats and marine resources of cultural and ecological importance throughout the ancestral waters of the Salish Sea. This report describes the Coast Salish Tribal Journey Water Quality Project, its inception, the results of the 2008 Tribal Journey project, lessons learned, and recommendations for future directions.

Report↗
USGS2009

Satellite telemetry of marine megavertebrates: The coming of age of an experimental science

Wildlife telemetry research has expanded greatly in the last 2 decades, with the application of satellite tracking and archival logging technologies to study the ecology and conservation of marine mammals, birds, fishes, and turtles. Widespread and expanding use of satellite tracking to study movements and habitats of marine megavertebrates warrants a review of progress to date and a discussion of challenges facing this rapidly evolving research field. To this end, we reviewed the satellite telemetry literature of air-breathing marine taxa (i.e. birds, mammals, turtles) over the 20 yr time period from 1987 to 2006. This review yielded 92 studies with a wide taxonomic representation: 47 seabirds, 23 sea turtles, and 22 marine mammals. Here we critically evaluate these articles to assess progress in satellite tracking of marine megavertebrates in terms of (1) objectives and approach, (2) experimental design, and (3) reporting of results. The overall trends revealed increases in the duration and scope of tracking studies, yet improvements on experimental design and reporting are needed to facilitate comparisons across studies and species. While inherent ecological differences influence the focus and methods of taxon-specific studies, this review highlights specific areas in need of improvement and provides general suggestions for future tracking studies of marine megavertebrates.

Endangered Species Research↗
USGS2019

Measurement of sounds emitted by certain high-resolution geophysical survey systems

Scientific questions regarding the impact of anthropomorphic noise in the marine environment have resulted in an increasing number of regulatory requirements and precautionary mitigation strategies to reduce the risks associated with high-resolution marine geophysical surveys performed in waters subjected to government jurisdiction. An example of regulatory frameworks includes the Marine Mammal Protection Act in the United States and the Marine Strategy Framework Directive 2008/56/EC in the European Union. Regulatory compliance often requires an assessment of the potential ecological risks before initiating a marine geophysical survey. However, the acoustic source data needed to estimate the risk associated with the operation of a given high-resolution survey system are frequently lacking. A comprehensive measurement program was performed to quantify the characteristics of sounds radiated by a variety of commercial marine geophysical survey systems, including boomers, sparkers, airguns, chirp sub-bottom profilers, sidescan sonars, and swath-bathymetric sonars [Crocker and Fratantonio, “Characteristics of high-frequency sounds emitted during high-resolution marine geophysical surveys,” Naval Undersea Warfare Center, Newport, RI, USA, NUWC-NPT Tech. Rep. 12, 203, 2016]. Calibrated acoustic source data, including source levels, source spectra, and beam patterns, were acquired for a total of 18 different marine geophysical survey systems. The data support modeling to estimate the potential ecological impacts resulting from the operation of certain high-resolution marine geophysical survey systems.

IEEE Journal of Oceanic Engineering↗
USGS2020

Spatial and temporal dynamics of Pacific capelin Mallotus catervarius in the Gulf of Alaska: Implications for ecosystem-based fisheries management

Pacific capelin Mallotus catervarius are planktivorous, small pelagic fish that serve an intermediate trophic role in marine food webs. Due to the lack of a directed fishery or monitoring of capelin in the Northeast Pacific, there is limited information on their distribution and abundance, and how spatio-temporal fluctuations in capelin density affects their availability as prey. To provide information on life history, spatial patterns, and population dynamics of capelin in the Gulf of Alaska (GOA), we modeled distributions of spawning habitat and larval dispersal, and synthesized spatially-indexed data from multiple, independent sources from 1996 to 2016. Potential capelin spawning areas were broadly distributed across the GOA. Models of larval drift show the GOA’s advective circulation patterns disperse capelin larvae over the continental shelf and upper slope, indicating potential connections between spawning areas and observed offshore distributions that are influenced by the location and timing of spawning. Spatial overlap in composite distributions of larval and age-1+ fish was used to identify core areas where capelin consistently occur and concentrate. Capelin primarily occupy shelf waters near the Kodiak Archipelago, and are patchily distributed across the GOA shelf and inshore waters. Interannual variations in abundance along with spatio-temporal differences in density indicates the availability of capelin to predators and monitoring surveys is highly variable in the GOA. We demonstrate that the limitations of individual data series can be compensated for by integrating multiple data sources to monitor fluctuations in distributions and abundance trends of an ecologically important species across a large marine ecosystem.

Alaska↗
USGS2010

Kinetics of viral shedding provide insights into the epidemiology of viral hemorrhagic septicemia in Pacific herring

Losses from infectious diseases are an important component of natural mortality among marine fish species, but factors controlling the ecology of these diseases and their potential responses to anthropogenic changes are poorly understood. We used viral hemorrhagic septicemia virus (VHSV) and a laboratory stock of Pacific herring Clupea pallasii to investigate the kinetics of viral shedding and its effect on disease transmission and host mortality. Outbreaks of acute disease, accompanied by mortality and viral shedding, were initiated after waterborne exposure of herring to concentrations of VHSV as low as 101 plaque-forming units (pfu) ml–1. Shed virus in flow-through tanks was first detected 4 to 5 d post-exposure, peaked after 6 to 10 d, and was no longer detected after 16 d. Shedding rates, calculated from density, flow and waterborne virus titer reached 1.8 to 5.0 × 108 pfu fish–1 d–1. Onset of viral shedding was dose-dependent and preceded initial mortality by 2 d. At 21 d, cumulative mortality in treatment groups ranged from 81 to 100% and was dependent not on challenge dose, but on the kinetics and level of viral shedding by infected fish in the tank. Possible consequences of the viral shedding and disease kinetics are discussed in the context of epizootic initiation and perpetuation among populations of wild Pacific herring.

Marine Ecology Progress Series↗
USGS2016

Detecting spatial regimes in ecosystems

Research on early warning indicators has generally focused on assessing temporal transitions with limited application of these methods to detecting spatial regimes. Traditional spatial boundary detection procedures that result in ecoregion maps are typically based on ecological potential (i.e. potential vegetation), and often fail to account for ongoing changes due to stressors such as land use change and climate change and their effects on plant and animal communities. We use Fisher information, an information theory-based method, on both terrestrial and aquatic animal data (U.S. Breeding Bird Survey and marine zooplankton) to identify ecological boundaries, and compare our results to traditional early warning indicators, conventional ecoregion maps and multivariate analyses such as nMDS and cluster analysis. We successfully detected spatial regimes and transitions in both terrestrial and aquatic systems using Fisher information. Furthermore, Fisher information provided explicit spatial information about community change that is absent from other multivariate approaches. Our results suggest that defining spatial regimes based on animal communities may better reflect ecological reality than do traditional ecoregion maps, especially in our current era of rapid and unpredictable ecological change.

Ecology Letters↗