Jory Cabrol

Fisheries and Oceans Canada | DFO · Maurice Lamontagne Institute (MLI)

Different krill species have a pivotal position in many marine food webs by both preying upon several tro-phic levels and being forage species for consumers. Within these food webs, different krill species coexist, though it remains unclear what mechanisms allow for the coexistence, for instance, of northern krill species in subarctic environments....

Krill, as forage species, play a pivotal role in marine food webs by linking lower to upper trophic levels. Despite their ecological relevance, processes affecting their physiological condition and their feeding selectivity remain not well known. Here, we hypothesize that significant spatial fluctuations of environmental conditions in a Subarctic r...

Krill species play a pivotal role in energetic transfer from lower to upper trophic levels. However, functional feeding responses, which determine how food availability influences ingestion rates, are still not well defined for northern krill species. Here, we estimated and compared the functional feeding responses on natural communities of phytopl...

The goal of this study was to evaluate and compare the short-term performances and the physiological plasticity of two cryptic species Eurytemora carolleeae and Eurytemora affinis (North-Atlantic clade) by simulating rapid advection from freshwater to brackish water conditions and reciprocally. To do so, two reciprocal transplant experiments withou...

The cryptic species complex, Eurytemora affinis is an important component of the mesozooplankton of estuarine transition zones (ETZs). In the St Lawrence ETZ, two clades, the Atlantic and the North-Atlantic clades co-occur. However, their distribution along environmental gradients is spatially segregated, potentially because of differential habitat...

Documenting long-term changes in the trophic structure of food webs and how species respond to these changes is essential to forecast their vulnerability and resilience to environmental stressors. Over the past decades, the St. Lawrence marine ecosystem (Canada) has experienced major changes in its physical, chemical, and biological conditions from...

Lipids are naturally depleted in ¹³ C isotope in relation to its C sources, causing a bias in δ ¹³ C in bulk samples that varies with lipid content. Failure to take this issue into account results in inaccurate conclusions in food web and habitat use studies. Two approaches to resolve this issue are 1) to extract lipids from samples prior to measur...

Toxoplasmosis is a parasitic disease caused by the zoonotic protozoan Toxoplasma gondii. This parasite, whose definitive hosts are Felidae, including domestic cats, can cause fatal systemic infections in juveniles and adults of various animal species. During primary in-utero infection, T. gondii can, among other things, cause embryonic resorptions,...

Very high levels of industrial contaminants in St. Lawrence Estuary (SLE) beluga whales represent one of the major threats to this population classified as endangered under the Species at Risk Act in Canada. Elevated concentrations of short-chained chlorinated paraffins (SCCPs) were recently reported in blubber of adult male SLE belugas. SCCPs are...

Very high levels of industrial contaminants in St. Lawrence Estuary (SLE) beluga whales represent one of the major threats to this population classified as endangered under the Species at Risk Act in Canada. Elevated concentrations of short-chained chlorinated paraffins (SCCPs) were recently reported in blubber of adult male SLE belugas. Recent reg...

This study sought to estimate the effect of an anthropogenic and climate-driven change in prey availability on the degree of individual and population specialization of a large marine predator, the fin whale ( Balaenoptera physalus ). We examined skin biopsies from 99 fin whales sampled in the St. Lawrence Estuary (Canada) over a nine year period (...

Description This study sought to estimate the effect of an anthropogenic and climate-driven change in prey availability on the degree of individual and population specialization of a large marine predator, the fin whale (Balaenoptera physalus) in the estuary and the gulf of St. Lawrence (eastern Canada). Specifically, we here examine the trophic ni...

The endangered St. Lawrence Estuary (SLE) beluga population is declining and has shown no sign of recovery over the past decades despite several protective measures. Changes in the availability of food resources and exposure to organohalogen contaminants have been suggested as potential factors limiting the recovery of this population. Studies on S...

The Nordic krill Meganyctiphanes norvegica and Arctic krill Thysanoessa raschii both dominate the krill community within the Estuary and Gulf of St. Lawrence system where they are central forage species for its pelagic ecosystem. We developed a species‐specific physiological individual based model that implements the critical physiological processe...

Spatio-temporal variations of the physiological condition and the feeding behaviour of Meganyctiphanes norvegica in the gulf of St. Lawrence

In subarctic ecosystems, the krill communities are composed of many species, ranging from temperate to arctic, with diverse morphology and ecology. These krill species may express differential eco-physiological traits, which in turn may vary with strong seasonal changes in temperature and food supply in these environments. To enhance our capacity t...

Le copepode calanoide Eurytemora affinis est un complexe d’especes cles des reseaux trophiques estuariens. En dominant les communautes planctoniques dans la plupart des estuaires de l’hemisphere nord, E. affinis permet un transfert d’energies vers les niveaux trophiques superieurs. Il influence directement le recrutement des especes de poissons et...

Krill as forage species play a key role in energy transfer to higher trophic levels in marine ecosystems. In the St. Lawrence estuary, three krill species (Meganyctiphanes norvegica, Thysanoessa raschii, Thysanoessa inermis) coexist and dominate the macrozooplankton biomass. Although, these species are ecologically important, the dynamics of their...

The St. Lawrence estuarine transition zone includes the interface between the freshwater and the brackish. The euryhaline and dominant copepod Eurytemora affinis occurs throughout the entire transition zone, but E. affinis is a sibling species complex with two morphologically similar but genetically distinct clades. The E. caroleeae and the North-A...

The lower St. Lawrence estuary (LSLE) is influenced by river discharge and saltwater inflow. Together with arctic water inflow and ice cover in winter, a strong stratification occurs resulting in a cold intermediate layer (CIL) from spring to autumn. This stratification provides thermal habitats. Here, we focus on two krill species Thysanoessa rasc...

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The family Oscarellidae is one of the two families in the class Homoscleromorpha (phylum Porifera) and is characterized by the absence of a skeleton and the presence of a specific mitochondrial gene, tatC. This family currently encompasses sponges in two genera: Oscarella with 17 described species and Pseudocorticium with one described species. Alt...

Mesquite matrix for some morphological characters from Tables 2 and 3. Characters and characters-states are detailed. (PDF)

Mesquite matrix for V4 secondary structures for 18S rDNA. (PDF)