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Drying Spring Accelerates Transitions Toward Pyrogenic Vegetation in Eastern Boreal North AmericaNARA Subscribed
The ongoing climate change increases vegetation flammability in the boreal forests of eastern North America, leading to more intense and severe wildfires. Using palaeoecological data—including charcoal, pollen, chironomids and testate amoebae—and climate model simulations of vapour pressure deficit (VPD) and available soil water (ASW), we analysed fire dynamics over the past 8000 years in boreal eastern North America. Over the...
Cover Image, Volume 28, Issue 6NARA Subscribed
Shape plasticity in response to water velocity in the freshwater blenny Salaria fluviatilisNARA Subscribed
A non‐random association between an environmental factor and a given trait could be explained by directional selection (genetic determinism) and by phenotypic plasticity (environmental determinism). A previous study showed a significant relationship between morphology and water velocity in Salaria fluviatilis that conformed to functional expectations. The objective of this study was to test whether this relationship could be e...
The first goal of this study was to determine whether morphological variation in the freshwater blenny Salaria fluviatilis results in spatially structured populations distributed around Corsica, France, which would suggest genetically differentiated populations through reproductive isolation by distance. The second goal was to determine whether some morphological traits are related to water velocity, one of the most contrastin...
Does predation risk influence habitat use by northern redbelly dace Phoxinus eos at different spatial scales?NARA Subscribed
This study investigated the relationship between spatial variations in predation risk and abundance of northern redbelly dace Phoxinus eos at both macroscale (littoral v. pelagic zones) and microscale (structured v. open water habitats in the littoral zone) of Canadian Shield lakes. Minnow traps were placed in both structured and open water habitats in the littoral zone of 13 Canadian Shield lakes, and estimates of the relativ...
Effects of dynamic landscape elements on fish dispersal: the example of creek chub ( Semotilus atromaculatus )NARA Subscribed
Barriers along a watercourse and interconnections between drainage systems are dynamic landscape elements that are expected to play major roles in the dispersal and genetic structure of fish species. The objective of this study was to assess the role of these elements using creek chub ( Semotilus atromaculatus ) in the Mastigouche Wildlife Reserve (Québec, Canada) as model. Numerous impassable waterfalls and interconnections a...
Stomach contents, parasite assemblages and morphometrics were compared in brook charr Salvelinus fontinalis from the littoral and pelagic zone of two adjacent lakes on the Canadian Shield. In lac Baie des Onze Îles, fish from the littoral zone had greater abundance of benthic prey in their stomach and were more heavily infected by parasites that use intermediate hosts associated with the littoral zone than fish captured in the...
Growth and condition of piscivorous and non‐piscivorous walleye Sander vitreus classified on the basis of their stomach contents were compared to assess the consequences of their trophic flexibility. Piscivorous males showed a significantly higher growth trajectory than non‐piscivorous ones, while there was no difference in the growth of females. No differences were found in the condition of piscivorous and non‐piscivorous wal...
Differential time budgets of two forms of juvenile brook charr in the open‐water zoneNARA Subscribed
No significant differences were found in the time budget (time spent in feeding, moving and stationary), attack rate (number of feeding bouts min −1 ), and microhabitat use of juvenile (1+ years) littoral and pelagic brook charr Salvelinus fontinalis at 2 and 4 m depth, when restricted to feeding in pelagic enclosures. In contrast, fish of the littoral form allocated significantly more time than pelagic ones to feeding, moving...
Genetic data suggest that the littoral and pelagic forms of brook charr Salvelinus fontinalis in Lake Bondi are two populations with partial reproductive isolation and non‐random mating. Genetic differentiation between the two groups was supported by differences in allele frequencies and by deviation from Hardy‐Weinberg equilibrium when the two groups were pooled; no such deviation was observed when fish were divided into litt...
The specific objectives of this study were to determine if there is individual specialization in habitat use by lacustrine brook charr Salvelinus fontinalis and if so, if specialization is related to fish morphology. Localizations of 28 brook charr equipped with thermosensitive radiotransmitters were recorded during three summers (1991, 1992, and 1993) in two lakes of the Mastigouche Reserve (Québec, Canada). Fifty per cent of...
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