Dominance and size affect foraging position choice by Arctic grayling (Thymallus arcticus).

Salmonid fishes are a widespread and economically important group of fishes that are strongly affected by anthropogenic environmental degradation. Consequently, studies on their behavior and ecology are essential for their conservation. Wild Arctic grayling (Thymallus arcticus) were observed in an unimpacted Alaskan river using underwater video observations for two consecutive summers (2015 and 2016).

BioTIME: A database of biodiversity time series for the Anthropocene.

Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time series.

Detecting temporal trends in species assemblages with bootstrapping procedures and hierarchical models.

Quantifying patterns of temporal trends in species assemblages is an important analytical challenge in community ecology. We describe methods of analysis that can be applied to a matrix of counts of individuals that is organized by species (rows) and time-ordered sampling periods (columns). We first developed a bootstrapping procedure to test the null hypothesis of random sampling from a stationary species abundance distribution with temporally varying sampling probabilities.

Estimating differential reproductive success from nests of related individuals, with application to a study of the mottled sculpin, Cottus bairdi.

Understanding how variation in reproductive success is related to demography is a critical component in understanding the life history of an organism. Parentage analysis using molecular markers can be used to estimate the reproductive success of different groups of individuals in natural populations. Previous models have been developed for cases where offspring are random samples from the population but these models do not account for the presence of full- and half-sibs commonly found in large clutches of many organisms.

Form and performance: body shape and prey-capture success in four drift-feeding minnows.

Identifying links between morphology and performance for ecologically relevant tasks will help elucidate the relationships between organismal design and fitness. We conducted a laboratory study to quantify the relationship between variation in body shape and prey-capture success in four drift-feeding minnow species. We offered drifting prey to individual fish in a test flume, counted successful strikes to measure prey-capture success and recorded the position (X, Y coordinates) of ten landmarks on each fish's outline to delineate the specimen's form.

Intensive genetic assessment of the mating system and reproductive success in a semi-closed population of the mottled sculpin, Cottus bairdi.

Most genetic surveys of parentage in nature sample only a small fraction of the breeding population. Here we apply microsatellite markers to deduce the genetic mating system and assess the reproductive success of females and males in an extensively collected, semi-closed stream population of the mottled sculpin fish, Cottus bairdi. In this species, males guard nest rocks where females deposit the eggs for fertilization.

Food, fights, and burrows: The adaptive significance of intraspecific aggression in the bay goby (Pisces: Gobiidae).

The effects of size, sex, bout initiation, past experience, and prior residence were examined with respect to the outcome of intraspecific agonistic contests in the bay goby (Lepidogobius lepidus). In addition, the adaptive significance of this behavior was examined by investigating the relationship between dominance and access to two potentially limiting resources; food and the burrows of invertebrate symbionts.For heterosexual and male homosexual contests, size and initiation significantly affected bout outcome.

Ecological aspects of ontogenetic shifts in prey size utilization in the bay goby (Pisces: Gobiidae).

Two age classes (0+ to 3+ and 4+ to 7+) of bay gobies (Lepidogobius lepidus Girard) differed in the sizes of whole prey (except polychaetes) recovered from the digestive tract. Although older fish consumed greater amounts of larger prey they did not capture larger individuals of a given prey type for seven of nine prey classes. The remaining two, harpacticoid copepods and ostracods contribute minimally to ontogenetic differences.