EEOB Publications September 1 - September 30
Species Distribution Models for a Native Imperiled Minnow and a Nonnative Sport Fish in a Western Ohio River
Kenneth J. Oswald, Sophia Beery, Kalyn Rossiter, Yong Wang, Marc R. Kibbey. North Amer J of Fisheries Management (2020). https://doi.org/10.1002/nafm.10488
Sport fisheries are frequent drivers of nonnative fish introductions throughout the inland waters of North America. These fisheries often value aggressive, large‐bodied predators, and although they satiate angling demand they are also potentially problematic in systems that support imperiled species. The Tonguetied Minnow Exoglossum laurae is a rare species that maintains a disjunct distribution across small portions of four watersheds in the eastern and Midwestern United States, all of which are stocked with nonnative Brown Trout Salmo trutta for sportfishing. This study estimated habitat preferences for Tonguetied Minnow and Brown Trout in the Great Miami River, the westernmost drainage within the Tonguetied Minnow’s range. Model data were based on eight water quality variables and seven stream habitat variables. Negative binomial regressions identified gradient, maximum water temperature, substrate, pool/glide habitat, total dissolved solids, and specific conductance as important predictors of the distribution of Tonguetied Minnow, whereas maximum water temperature and substrate were identified for Brown Trout. These reduced numbers of variables then served as input into maximum entropy species distribution models for Tonguetied Minnow and Brown Trout. Only gradient (model contribution [MC] = 46.9%; permutation importance [PI] = 11.6%) and maximum water temperature (MC = 44.2%; PI = 79.8%) contributed substantially to the species distribution model for Tonguetied Minnow, while maximum water temperature (MC = 63.4%; PI = 76.2%) and substrate (MC = 36.6%; PI = 23.8%) were important contributors for Brown Trout. Water temperature appears to exert the principal influence on the distributions of both species and supports the premise that these species share similar habitat preferences within the Great Miami River. Therefore, the Tonguetied Minnow is likely unable to avoid interspecific interactions, such as predation, posed by Brown Trout that are introduced for sportfishing, thus raising concerns about the conservation of this isolated and highly imperiled population.
Mediators of invasions in the sea: life history strategies and dispersal vectors facilitating global sea anemone introductions
Heather Glon, Marymegan Daly, James T. Carlton, Megan M. Flenniken & Zara Currimjee. Biol Invasions (2020). https://doi.org/10.1007/s10530-020-02321-6
Widespread non-native species tend to demonstrate an apparent lack of selectivity in habitat requirements, feeding regimes, and reproductive needs, while displaying a tendency to thrive in human-modified habitats. The high phenotypic plasticity typical of sessile, substrate-attached marine species may enhance their chances of survival and spread in a new region. Anthropogenic activities have changed marine habitats over a wide range of phenomena, including water temperature, community species composition, and the types of available substrates, creating new physical and biotic regimes that may contribute to the potential for successful species introduction. Here we examine ten species of sea anemones that have been introduced outside of their native range, and elucidate specific characteristics that are common among globally introduced sea anemones. Various life history strategies enable these species to survive and flourish through transport, introduction, establishment and spread, leading to the successful colonization of a new geographic area. Considering life history strategies and weighing of vector potential, we suggest conditions that facilitate introduction of these species, and identify species of sea anemones that may be introduced in the future in the face of changing climate and increased anthropogenic activities.