Selina S. Heppell

Selina S. Heppell
Oregon State University | OSU · Department of Fisheries and Wildlife

PhD

About

98
Publications
33,657
Reads
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5,281
Citations
Additional affiliations
January 2001 - present
Oregon State University
Position
  • Associate Department Head
July 1998 - July 2003
Duke University Marine Lab
Position
  • Instructor
April 1995 - May 1998
Duke University
Position
  • Graduate Student and Instructor
Description
  • Also instructor in 1999, 2000, 2001 and 2002

Publications

Publications (98)
Article
Full-text available
Characterizing the behavior of coral reef fishes at home reef sites can provide insight into the mechanisms of spatial ecology and provide a framework for spatial resource management. In the Caribbean, populations of Nassau grouper Epinephelus striatus have declined due to fishing impacts on spawning aggregations. Despite local and regional efforts...
Article
For species of conservation concern, somatic growth and age at maturation are key parameters in models used to evaluate population dynamics, as spatial and temporal variability in growth rates may be particularly important for predicting population recovery. Following an oceanic juvenile developmental stage, endangered Kemp’s ridley sea turtles Lep...
Article
Full-text available
Many environmental processes influence animal somatic growth rates. However, elucidating specific drivers of somatic growth variation has been challenging for marine megafauna. Using a 20+ year dataset of somatic growth generated through skeletochronology, we evaluated the relationship between multiple region-wide environmental factors-the Deepwate...
Article
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Reptile growth is influenced by many ecological processes that can cumulatively give rise to divergent somatic growth rates within spatially structured populations. As somatic growth variation can strongly influence a species’ population dynamics, identifying proximate drivers can be critical to the conservation and management of protected species....
Article
For stochastic growth processes, integrated mixed-effects (IME) models of capture-recapture data and size-at-age data from calcified structures such as otoliths can reduce bias in model parameters. Researchers have not fully explored the performance of IME models for simultaneously estimating the unknown ages, growth model parameters, and derived v...
Article
Full-text available
Population monitoring must be accurate and reliable to correctly classify population status. For sea turtles, nesting beach surveys are often the only population‐level surveys that are accessible. However, process and observation errors, compounded by delayed maturity, obscure the relationship between trends on the nesting beach and the population....
Article
Full-text available
Determining the ecological roles that fishes play in the complex trophic relationships of coral reef systems depends on our ability to detect changes in the fish community composition and function. The functional redundancy of fishes in different habitats is highly influenced by species composition and ontogenetic shifts in diets and feeding behavi...
Article
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Functional diversity (FD) metrics quantify the trait diversity in biological assemblages and act as a proxy for the diverse ecological functions performed in the community. Analyses of FD offer a potentially useful tool to identify functional changes in diverse, complex, and disturbed marine ecosystems such as coral reefs, yet this metric is rarely...
Article
Full-text available
Despite evidence of maternal age effects in a number of teleost species, there have been challenges to the assertion that maternal age intrinsically influences offspring quality. From an evolutionary perspective, maternal age effects result in young females paradoxically investing in less fit offspring despite a greater potential fitness benefit th...
Article
Trace element analysis has emerged as a powerful tool to elucidate past movement and habitat use in aquatic animals, but has been underutilized in studies of non-fish species. When applied to sequentially deposited tissues (e.g. fish otoliths, sea turtle humerus bone), the technique can be used to infer aspects of an individual’s ecology through ti...
Article
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Ontogenetic niche theory predicts that individuals may undergo one or more changes in habitat or diet throughout their lifetime to maintain optimal growth rates, or to optimize trade-offs between mortality risk and growth. We combine skeletochronological and stable nitrogen isotope (δ¹⁵N) analyses of sea turtle humeri (n = 61) to characterize the g...
Article
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Marine fisheries science is a broad field that is fundamentally concerned with sustainability across ecological, economic, and social dimensions. Ensuring the delivery of food, security, equity, and well-being while sustaining ecosystems in the face of rapid change is, by far, the main challenge facing marine fisheries. A tighter integration of mod...
Article
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Distinguishing individual natal origins of highly dispersive species is essential for quantifying the extent of connectivity among spatially separated groups. Variation in the chemical composition of calcified structures has been used to determine natal origins of many organisms but the utility of this approach to sharks and rays has only recently...
Article
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Mediterranean populations of loggerhead Caretta caretta and green sea turtles Chelonia mydas are subject to several anthropogenic threats, with documented mortality from incidental capture in fishing gear. However, how such mortalities actually affect the populations is uncertain without an estimate of population size. We derived a theoretical demo...
Article
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In the Eastern Tropical Pacific (ETP), a region of high fishing activity, olive ridley (Lepidochelis olivacea) and other sea turtles are accidentally caught in fishing nets with tuna and other animals. To date, the interaction between fishing activity, ocean conditions and sea turtle incidental catch in the ETP has been described and quantified, bu...
Article
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Multiple populations of green sea turtles Chelonia mydas show signs of population recovery. In Hawaii (USA), green turtles have increased 5.4% yr⁻¹ since 1973, but fluctuations in census counts of nesting females make recovery diagnosis difficult. Evaluating demographic rates for temporal change and in relation to population density, and indicators...
Article
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We review the current practices of podocnemidid turtle conservation programs in South America and summarize the direct and indirect negative consequences that some of these practices may have on the populations we are attempting to manage. We argue that programs that only focus on nest transfer and head-starting as their conservation strategies wou...
Article
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We conducted a four-year study of the life history parameters of the endangered freshwater turtle Podocnemis lewyana (Testudines: Podocnemididae) in four channels connecting wetlands to the Magdalena River in northern Colombia. Using capture-mark-recapture techniques, we documented body size growth rates, sex ratios, and size class distributions, a...
Article
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Ontogenetic changes in resource use often delimit transitions between life stages. Ecological and individual factors can cause variation in the timing and consistency of these transitions, ultimately affecting community and population dynamics through changes in growth and survival. Therefore, it is important to document and understand behavioral a...
Article
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While there is a persistent inverse relationship between latitude and species diversity across many taxa and ecosystems, deviations from this norm offer an opportunity to understand the conditions that contribute to large-scale diversity patterns. Marine systems, in particular, provide such an opportunity, as marine diversity does not always follow...
Article
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With the ongoing crisis of biodiversity loss and limited resources for conservation, the concept of biodiversity hotspots has been useful in determining conservation priority areas. However, there has been limited research into how temporal variability in biodiversity may influence conservation area prioritization. To address this information gap,...
Article
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Temperate nearshore reefs along the Pacific coast of North America are highly valuable to commercial and recreational fisheries yet comprise a small fraction of the seabed. Monitoring fisheries resources in this region is difficult; high-relief structural complexity and adverse sea conditions have led to a paucity of information on temperate reef s...
Article
Individual quota (IQ) management systems in commercial marine fisheries are highly diverse, differing in the security, durability and exclusivity of the harvesting privilege and the transferability of quota units. This diversity in the degree of harvest rights may influence the effectiveness of IQ fisheries to meet management objectives. We conduct...
Article
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Many multispecies models have assumed that prey density determines per-capita predator consumption rates, following a functional response relationship. However, empirical evidence suggests that a predator's diet can also be influenced by a variety of environmental factors, including interactions with other predators. We used diet and abundance data...
Article
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In this article we consider the current educational needs for science and policy in marine resource management, and we propose a way to address them. The existing literature on cross-disciplinary education in response to pressing environmental problems is vast, particularly in conservation biology. However, actual changes in doctoral-level marine s...
Article
There is a global trend in the depletion of transient reef fish spawning aggregations ("FSAs"), making them a primary target for management with marine protected areas (MPAs). Here, we review the observed and likely effectiveness of FSA MPAs, discuss how future studies could fill knowledge gaps, and provide recommendations for MPA design based on s...
Article
Marine megafauna such as seabirds, marine mammals and sea turtles are subject to high mortality from incidental capture or bycatch in fisheries. Recent research suggests that fishing effort is increasing worldwide, highlighting the need to evaluate strategies intended to reduce marine megafauna bycatch. Here, we use three focal species (i.e. leathe...
Article
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The quality and quantity of data affect the reliability of all stock assessments. Over time, we expect data to improve and assessment predictions to become more reliable. There is a potential for strong bias in estimates of sustainable yield if the available data are not a good representation of stock dynamics, particularly for catch-based data-poo...
Article
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Fisheries bycatch threatens populations of marine megafauna such as marine mammals, turtles, seabirds, sharks and rays, but fisheries impacts on non-target populations are often difficult to assess due to factors such as data limitation, poorly defined management objectives and lack of quantitative bycatch reduction targets. Limit reference points...
Article
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Previous studies have shown that oceanographic conditions influence the distribution of range-expanding Humboldt squid (Dosidicus gigas), but broad-scale temporal and spatial distribution analyses are limited. Interannual variability in Humboldt squid occurrence is largely undocumented north of California. We combined annual occurrences noted by fi...
Article
Full-text available
Differences in the chemical composition of calcified skeletal structures (e.g. shells, otoliths) have proven useful for reconstructing the environmental history of many marine species. However, the extent to which ambient environmental conditions can be inferred from the elemental signatures within the vertebrae of elasmobranchs (sharks, skates, ra...
Article
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Determining the mechanisms responsible for the success of invasive species is critical for developing effective management strategies. Artificially draining managed wetlands to maintain natural ephemeral conditions is a common practice in the Pacific Northwest and is assumed to kill invasive American bullfrog (Lithobates catesbeianus) larvae, which...
Article
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Characterizing the behaviors of sea turtles and identifying high-use areas as they vary in time and space is important for conservation planning, particularly when turtles overlap with fisheries that may unintentionally harm them. Between July 2006 and March 2010, 27 satellite transmitters were deployed at sea on juvenile loggerheads Caretta carett...
Conference Paper
The study of biodiversity in marine ecosystems is challenging because the oceans are vast and highly variable in space and time. Long-term data sets collected by management agencies are an excellent resource for researchers because they cover large areas and rely on standardized sampling, while worldwide statistics on catch and fisheries management...
Technical Report
Full-text available
in its entirety for noncommercial purposes. To order additional copies of this publication, call 541-737-4849. This publication is available in an accessible format on our website at http://seagrant.oregonstate.edu/sgpubs/onlinepubs.html. For a complete list of Oregon Sea Grant publications, visit http://seagrant.oregonstate.edu/sgpubs.
Article
Fisheries management based on catch shares – divisions of annual fleet-wide quotas among individuals or groups – has been strongly supported for their economic benefits, but biological consequences have not been rigorously quantified. We used a global meta-analysis of 345 stocks to assess whether fisheries under catch shares were more likely to tra...
Conference Paper
Background/Question/Methods Patterns of biodiversity vary in space and time and are strongly influenced by human activities and climate conditions. Increasing human pressures on marine ecosystems and emphasis on ecosystem-based management (EBM) requires an evaluation of the drivers of biodiversity over large spatial scales. Specifically, we ask t...
Article
Full-text available
Rights-based approaches are potentially promising tools to meet conservation objectives in natural resource management. Here, we evaluated how population status and fishery production respond to catch shares, a rights-based policy instrument in fisheries whereby participants are granted a right to harvest a fraction of the allowable catch. By analy...
Article
Full-text available
Olive ridley sea turtles Lepidochelys olivacea exhibit synchronized nesting behavior that affects egg survival through a variety of mechanisms, including intra-specific nest destruction. This activity is difficult to quantify due to the frequency of arribadas (mass nesting events that occur over several days) and temporal overlap of incubation peri...
Article
Full-text available
Forage fish play a pivotal role in marine ecosystems and economies worldwide by sustaining many predators and fisheries directly and indirectly. We estimate global forage fish contributions to marine ecosystems through a synthesis of 72 published Ecopath models from around the world. Three distinct contributions of forage fish were examined: (i) th...
Article
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Loggerhead sea turtles Caretta caretta have been listed as threatened under the US Endangered Species Act since 1978, and a change in their listing status to endangered was recently under consideration. Estimates of adult population size are needed to evaluate population status, but include a number of uncertainties. A point estimate of loggerhead...
Conference Paper
Forage fish are an integral part of marine ecosystems, providing prey to many species in the food web and linking upper and lower trophic levels. They are also targeted by fisheries around the world, with increasing pressure as the demand for seafood products escalates. A pertinent goal, therefore, is to implement management measures that take into...
Conference Paper
Modeling ecosystem dynamics and implementation of ecosystem management has become a research priority in marine fisheries. A wide variety of approaches have been taken to model fisheries in a multispecies framework. However, most previous efforts in modeling inter-species interactions have been somewhat restricted in the functional form of predator...
Presentation
Differences in the chemical composition of calcified structures are used to reconstruct environmental history and reveal natal origins, dispersal patterns, and metapopulation structure of many marine organisms. Because the use of discrete nursery areas is common among elasmobranchs, distinctive chemical markers may be incorporated into the vertebra...
Article
Full-text available
In the wake of the BP oil spill, U.S. agencies need research plans to collect data that will aid in managing and assessing marine species and ecosystems.
Article
Most shallow-dwelling tropical marine fishes exhibit different activity patterns during the day and night but show similar transition behavior among habitat sites despite the dissimilar assemblages of the species. However, changes in species abundance, distribution, and activity patterns have only rarely been examined in temperate deepwater habitat...
Article
Maternal effects are increasingly recognized as important drivers of population dynamics and determinants of evolutionary trajectories. Recently, there has been a proliferation of studies finding or citing a positive relationship between maternal size/age and offspring size or offspring quality. The relationship between maternal phenotype and offsp...
Article
Changes in the behavior of individual animals in response to environmental characteristics can provide important information about habitat preference, as well as the relative risk that animals may face based on the amount of time spent in hazardous areas. We analyzed movement and habitat affinities of ten loggerhead turtles (Caretta caretta) tagged...
Article
Full-text available
Lipids and fatty acids (FA) were investigated in 4 species of forage fish: northern anchovy Engraulis mordax, Pacific sardine Sardinops sagax, Pacific herring Clupea pallasi, and whitebait smelt Allosmerus elongatus, for their ability to serve as biological indicators of ocean conditions in the California Current large marine ecosystem (CCLME). Sam...
Article
Full-text available
The habitat needs of nearshore juvenile rockfish Sebastes spp. have rarely been studied but are an essential component of habitat identification for management. We investigated the relationships between habitat type, species composition, and growth of juvenile rockfish after settlement into nearshore reefs and estuaries in central Oregon. We identi...
Article
Population viability analysis (PVA) to forecast extinction risk is a commonly used tool in decision- and policy-making processes of governments and conservation organizations. A drawback to PVA is the high degree of uncertainty in these forecasts due to both population stochasticity and parameter estimation uncertainty. With sparse or noisy data, e...