14 Works

Data from: Baseline glucocorticoids are drivers of body mass gain in a diving seabird

Holly L. Hennin, Alicia M. Wells-Berlin & Oliver P. Love
Life-history trade-offs are influenced by variation in individual state, with individuals in better condition often completing life-history stages with greater success. Although resource accrual significantly impacts key life-history decisions such as the timing of reproduction, little is known about the underlying mechanisms driving resource accumulation. Baseline corticosterone (CORT, the primary avian glucocorticoid) mediates daily and seasonal energetics, responds to changes in food availability, and has been linked to foraging behavior, making it a strong potential...

Data from: Possible ballast water transfer of lionfish to the eastern Pacific Ocean

Hugh J. MacIsaac, Emma M. De Roy, Brian Leung, Alice Grgicak-Mannion & Gregory M. Ruiz
The Indo-Pacific Red Lionfish was first reported off the Florida coast in 1985, following which it has spread across much of the SE USA, Gulf of Mexico, and Caribbean Sea. Lionfish negatively impact fish and invertebrate assemblages and abundances, thus further spread is cause for concern. To date, the fish has not been reported on the Pacific coast of North or Central America. Here we examine the possibility of ballast water transfer of lionfish from...

Data from: Two-current choice flumes for testing avoidance and preference in aquatic animals

Fredrik Jutfelt, Josefin Sundin, Graham D. Raby, Anna-Sara Krång & Timothy D. Clark
Aquatic chemical ecology is an important and growing field of research that involves understanding how organisms perceive and respond to chemical cues in their environment. Research assessing the preference or avoidance of a water source containing specific chemical cues has increased in popularity in recent years, and a variety of methods have been described in the scientific literature. Two-current choice flumes have seen the greatest increase in popularity, perhaps because of their potential to address...

Data from: Post-spawning sexual selection in red and white Chinook salmon (Oncorhynchus tshawytscha)

Sarah J. Lehnert, Daniel D. Heath, Robert H. Devlin & Trevor E. Pitcher
Post-copulatory processes, including sperm competition and cryptic female choice (CFC), can play important roles in the maintenance of polymorphisms. In Chinook salmon (Oncorhynchus tshawytscha), color morphs (red and white) exist due to genetic polymorphisms affecting carotenoid deposition in flesh, skin, and gametes. We investigated the role of post-spawning sexual selection in maintaining the polymorphism in a mixed population. First, we compared sperm velocity differences in water between morphs. Next, we measured color-based CFC via 2...

Data from: Conservation implications of a lack of relationship between baseline glucocorticoids and fitness in a wild passerine

Christine L. Madliger & Oliver P. Love
The application of physiological measures to conservation monitoring has been gaining momentum and, while a suite of physiological traits are available to ascertain disturbance and condition in wildlife populations, glucocorticoids (i.e., GCs: cortisol and corticosterone) are the most heavily employed. The interpretation of GC levels as sensitive indicators of population change necessitates that GCs and metrics of population persistence are linked. However, the relationship between GCs and fitness may be highly context-dependent, changing direction, or...

Data from: Inbreeding effects on gene-specific DNA methylation among tissues of Chinook salmon

Clare J. Venney, Mattias L. Johansson & Daniel D. Heath
Inbreeding depression is the loss of fitness resulting from the mating of genetically related individuals. Traditionally, the study of inbreeding depression focused on genetic effects, although recent research has identified DNA methylation as also having a role in inbreeding effects. Since inbreeding depression and DNA methylation change with age and environmental stress, DNA methylation is a likely candidate for the regulation of genes associated with inbreeding depression. Here, we use a targeted, multigene approach to...

Data from: Evaluation of an acoustic telemetry transmitter designed to identify predation events

Edmund A. Halfyard, Dale Webber, Josh Del Papa, Todd Leadley, Steven T. Kessel, Scott F. Colborne & Aaron T. Fisk
The field of acoustic telemetry has evolved rapidly and now permits the remote sensing of animal behaviour, movement, physiology and survival in environments and species not previously possible. However, an inability to detect when a telemetered animal is consumed by a predator can complicate accurate interpretation of telemetry data. Here, we describe efforts to test two generations of a novel prototype acoustic telemetry transmitter designed specifically to detect predation. Testing involved either staged predation events...

Data from: Latitudinal variation in ecological opportunity and intraspecific competition indicates differences in niche variability and diet specialization of Arctic marine predators

David J. Yurkowski, Steve Ferguson, Emily S. Choy, Lisa L. Loseto, Tanya M. Brown, Derek C. G. Muir, Christina A. D. Semeniuk & Aaron T. Fisk
Individual specialization (IS), where individuals within populations irrespective of age, sex, and body size are either specialized or generalized in terms of resource use, has implications on ecological niches and food web structure. Niche size and degree of IS of near-top trophic-level marine predators have been little studied in polar regions or with latitude. We quantified the large-scale latitudinal variation of population- and individual-level niche size and IS in ringed seals (Pusa hispida) and beluga...

Data from: Residual eDNA detection sensitivity assessed by quantitative real-time PCR in a river ecosystem

Katherine D. Balasingham, Ryan P. Walter & Daniel D. Heath
Several studies have demonstrated that environmental DNA (eDNA) can be used to detect the presence of aquatic species, days to weeks after the target species has been removed. However, most studies used eDNA analysis in lentic systems (ponds or lakes), or in controlled laboratory experiments. While eDNA degrades rapidly in all aquatic systems, it also undergoes dilution effects and physical destruction in flowing systems, complicating detection in rivers. However, some eDNA (i.e. residual eDNA) can...

Data from: Sperm allocation in relation to female size in a semelparous salmonid

Yuya Makiguchi, Masaki Ichimura, Takenori Kitayama, Yuuki Kawabata, Takashi Kitagawa, Takahito Kojima & Trevor E. Pitcher
To maximize reproductive success, males have to adaptively tailor their sperm expenditure in relation to the quality of potential mates because they require time to replenish their sperm supply for subsequent mating opportunities. Therefore, in mating contexts where males must choose among females in a short period of time, as is the case with semelparous species (which die after one intensely competitive short duration breeding season), selection on sperm allocation can be expected to be...

Data from: Red and white Chinook salmon: genetic divergence and mate choice

Sarah J. Lehnert, Trevor E. Pitcher, Robert H. Devlin & Daniel D. Heath
Chinook salmon (Oncorhynchus tshawytscha) exhibit extreme differences in coloration of skin, eggs and flesh due to genetic polymorphisms affecting carotenoid deposition, where colour can range from white to bright red. A sympatric population of red and white Chinook salmon occurs in the Quesnel River, British Columbia, where frequencies of each phenotype are relatively equal. In our study, we examined evolutionary mechanisms responsible for the maintenance of the morphs, where we first tested whether morphs were...

Data from: Redder isn’t always better: cost of carotenoids in Chinook salmon eggs

Sarah J. Lehnert, Robert H. Devlin, Trevor E. Pitcher, Christina A.D. Semeniuk & Daniel D. Heath
Carotenoids provide animals with many fitness benefits through increased mating success, immune function, gamete quality, and antioxidant capacity. Despite these benefits, carotenoids are not utilized equally by all animals, implying trade-offs associated with the pigments; although, few studies have quantified fitness costs of carotenoid pigmentation. Salmon are known for their conspicuous red coloration; however, amongst Chinook salmon (Oncorhynchus tshawytscha), a natural genetic color polymorphism exists (red and white morphs) which results in carotenoid-based color differences...

Data from: Unpredictable perturbation reduces breeding propensity regardless of pre-laying reproductive readiness in a partial capital breeder

Pierre Legagneux, Holly L. Hennin, H. Grant Gilchrist, Tony D. Williams, Oliver P. Love & Joël Bêty
Theoretically, individuals of migratory species should optimize reproductive investment based on a combination of timing of and body condition at arrival on the breeding grounds. A minimum threshold body mass is required to initiate reproduction, and the timing of reaching this threshold is critical because of the trade-off between delaying breeding to gain in condition against the declining value of offspring with later reproductive timing. Long-lived species have the flexibility within their life history to...

Data from: Do baseline glucocorticoids simultaneously represent fitness and environmental quality in a declining aerial insectivore?

Christine L. Madliger & Oliver P. Love
Glucocorticoids (GCs) are often interpreted as indicators of disturbance, habitat quality, and fitness in wild populations. However, since most investigations have been unable to examine habitat variability, GC levels, and fitness simultaneously, such interpretations remain largely unvalidated. We combined a quantification of two habitat types, a manipulation of foraging ability (feather-clipping just prior to nestling rearing), multiple baseline plasma GC measures, and multi-year reproductive monitoring to experimentally examine the linkages between habitat quality, GCs, and...

Registration Year

  • 2016

Resource Types

  • Dataset


  • University of Windsor
  • Fisheries and Oceans Canada
  • Environment Canada
  • IVL Swedish Environmental Research Institute
  • University of Tasmania
  • McGill University
  • University of Gothenburg
  • Simon Fraser University
  • University of Manitoba
  • Smithsonian Environmental Research Center