Role of Nest Raiding and Egg Predation in Regulating Population Density of Threespine Sticklebacks (Gasterosteus aculeatus) in a Coastal British Columbia Lake

1989 ◽  
Vol 46 (3) ◽  
pp. 372-383 ◽  
Author(s):  
Kim D. Hyatt ◽  
Neil H. Ringler
Keyword(s):  
British Columbia ◽  
Population Density ◽  
Gasterosteus Aculeatus ◽  
Population Regulation ◽  
Egg Predation ◽  
Coastal Lake ◽  
Egg Consumption ◽  
Threespine Sticklebacks ◽  
Coastal British Columbia

The consequences of nest raiding and egg predation for population regulation of sticklebacks (Gasterosteus aculeatus) were studied in a British Columbia coastal lake. Stickleback eggs were present in the stomachs of 23 and 11% of all sticklebacks sampled from the field in 1982 and 1985 respectively. On average, males consumed more eggs than did females. Seasonal egg consumption increased with increases in stickleback density in breeding colonies. In experimental enclosure studies, nest densities varied between 0 and 3∙m−2 as stickleback numbers were manipulated from 1.5 to 12∙m−2. Peak nest densities occurred at 5.8 fish∙m−2. Stickleback density explained 70–86% of the variation in nest numbers in an application of a Ricker stock–recruit model and weekly rates of nest survival exhibited strong density dependence. Our evidence indicates that both nest raiding and egg cannibalism are important in limiting the production of stickleback fry as population density increases in scattered, lakeshore, breeding colonies of Kennedy Lake.

Egg cannibalism and the reproductive strategies of threespine sticklebacks (Gasterosteus aculeatus) in a coastal British Columbia lake

1989 ◽  
Vol 67 (8) ◽  
pp. 2036-2046 ◽  
Author(s):  
K. D. Hyatt ◽  
N. H. Ringler
Keyword(s):  
British Columbia ◽  
Gasterosteus Aculeatus ◽  
Filial Cannibalism ◽  
Substantial Part ◽  
Egg Cannibalism ◽  
Threespine Sticklebacks ◽  
Reproductive Cycles ◽  
Breeding Seasons ◽  
Free Ranging ◽  
Coastal British Columbia

Patterns of egg eating and their association with differences in sex, size, abundance, and reproductive status of free-ranging sticklebacks from Kennedy Lake, British Columbia, were examined as a means of identifying the relative importance of filial cannibalism or heterocannibalism as the source of eggs in the diet. Egg cannibalism was a common event: 23.0 and 11.2% of the sticklebacks examined in 1982 and 1985, respectively, had engaged in egg eating. Eggs were a substantial part of the overall diet of the stickleback population during two breeding seasons: 27.4% of the diet of all fish by weight in 1982, 32.8% of the diet by volume in 1985. Our results do not support Rohwer's contention that filial cannibalism is the source of most eggs in stickleback diets. Ten out of 11 predictions based on the filial cannibalism hypothesis were rejected, whereas the 11th was compatible with either the filial cannibalism hypothesis or the alternative heterocannibalism hypothesis. We conclude that heterocannibalism, not filial cannibalism, is the major source of eggs in the diet of Kennedy Lake sticklebacks. We suggest that nest raiding and egg cannibalism may minimize time spent foraging and maximize time spent on activities that increase the probability of initiating and successfully completing one or more reproductive cycles. Although the benefits of nest raiding and cannibalism are most obvious for populations breeding under conditions where food supplies clearly limit their potential reproductive output, the benefits may still apply even under conditions where alternative prey sources appear to be abundant.

“Boil them Hearts”

2016 ◽  
Vol 46 (1) ◽  
pp. 50-74
Author(s):  
Jason Redden
Keyword(s):  
Nineteenth Century ◽  
British Columbia ◽  
Indigenous Peoples ◽  
Scholarly Literature ◽  
Material Resources ◽  
Theoretical Inquiry ◽  
Critical Exploration ◽  
Coastal British Columbia ◽  
Academic Study

This paper addresses the academic conversation on Protestant missions to the Indigenous peoples of coastal British Columbia during the second half of the nineteenth century through a consideration of the role of revivalist piety in the conversion of some of the better known Indigenous Methodist evangelists identified in the scholarly literature. The paper introduces the work of existing scholars critically illuminating the reasons (religious convergence and/or the want of symbolic and material resources) typically given for Indigenous, namely, Ts’msyen, conversion. It also introduces Methodist revivalist piety and its instantiation in British Columbia. And, finally, it offers a critical exploration of revivalist piety and its role in conversion as set within a broader theoretical inquiry into the academic study of ritual and religion.

Evolutionary history of threespine sticklebacks (Gasterosteus spp.) in British Columbia: insights from a physiological clock

1995 ◽  
Vol 73 (11) ◽  
pp. 2154-2158 ◽  
Author(s):  
Rees Kassen ◽  
Dolph Schluter ◽  
John Donald McPhail
Keyword(s):  
British Columbia ◽  
Fresh Water ◽  
Evolutionary History ◽  
Egg Size ◽  
Gasterosteus Aculeatus ◽  
Salt Water ◽  
Freshwater Invasion ◽  
Freshwater Population ◽  
Threespine Sticklebacks ◽  
History Of

Geologic and allozyme evidence suggests that threespine sticklebacks (Gasterosteus aculeatus complex) in low-lying southwestern British Columbia lakes were founded during two incursions of marine sticklebacks after the retreat of the Pleistocene glaciers (the double-invasion hypothesis). We used the salinity tolerance of embryos, measured as hatchability in salt water, to establish the relative order of freshwater invasion by marine sticklebacks and to test the double-invasion hypothesis. Limnetics and an anadromous population hatched nearly equivalent numbers of young in salt water as in fresh water, whereas benthics and one solitary freshwater population had low hatchability in salt water. We also found that eggs from freshwater populations were larger than those from marine populations and limnetics had smaller eggs than benthics and the solitary population. These results support the double-invasion hypothesis and suggest a trend of increasing egg size with increasing time spent in fresh water.

Genetic variability in freshwater and anadromous sticklebacks (Gasterosteus aculeatus) of southern British Columbia

1985 ◽  
Vol 63 (3) ◽  
pp. 528-533 ◽  
Author(s):  
R. E. Withler ◽  
J. D. McPhail
Keyword(s):  
British Columbia ◽  
Gasterosteus Aculeatus ◽  
Electrophoretic Variation ◽  
Average Heterozygosity ◽  
Polymorphic Loci ◽  
Allelic Frequencies ◽  
Marine Habitats ◽  
Freshwater Habitats ◽  
Threespine Sticklebacks ◽  
Freshwater Stickleback

Electrophoretic variation at eight loci was compared between anadromous and freshwater populations of threespine sticklebacks (Gasterosteus aculeatus) collected from 56 sites in southwestern British Columbia and northwestern Washington. Allelic frequencies at five polymorphic loci were heterogeneous among populations and the average allelic frequencies at four loci differed between anadromous and freshwater sticklebacks. The average number of polymorphic loci was greater in anadromous (4.6) than in freshwater (3.2) populations. The average heterozygosity was 0.113 ± 0.001 in anadromous and 0.117 ± 0.003 in freshwater stickleback populations. Anadromous populations were more polymorphic but less heterogeneous than freshwater populations. The standardized genetic variance indicated only moderate differentiation among anadromous populations from marine habitats, but considerable differentiation among populations from freshwater habitats. Our data are consistent with the hypothesis of postglacial polyphyletic origins for freshwater populations of Gasterosteus, but also indicate that selection favours different alleles in marine and freshwater environments, at least at the Mdh-1 locus.

scholarly journals Two paradigms of population regulation

1995 ◽  
Vol 22 (1) ◽  
pp. 1 ◽  
Author(s):  
C. J. Krebs
Keyword(s):  
Population Density ◽  
Density Dependence ◽  
Population Regulation ◽  
Food Shortage ◽  
Holy Grail ◽  
Density Dependent ◽  
Movement Rates ◽  
Birth Death

No population increases without limit and ecologists have utilised two paradigms to find out why. The density-dependent paradigm assumes that birth, death and movement rates will be related to population density. In many cases they are not, and the search for density dependence has become a holy grail. A better approach is through the mechanistic paradigm which searches for relationships between birth, death and movement rates, and the mechanisms controlling populations, such as disease, predation, food shortage and territoriality. Seven suggestions are made for analysing the role of disease in population regulation in mammals. Useful progress will flow more quickly from the mechanistic paradigm without the need to search for density dependence.

scholarly journals Suppression of personality variation in boldness during foraging in three-spined sticklebacks

2021 ◽  
Vol 75 (4) ◽  
Author(s):  
Hannah E. A. MacGregor ◽  
Aislinn Cottage ◽  
Christos C. Ioannou
Keyword(s):  
Negative Feedback ◽  
Risk Taking ◽  
Positive Feedback ◽  
Gasterosteus Aculeatus ◽  
Control Treatment ◽  
Refuge Use ◽  
Individual Level ◽  
Behavioural Type ◽  
State Behaviour

Abstract Consistent inter-individual variation in behaviour within a population, widely referred to as personality variation, can be affected by environmental context. Feedbacks between an individual’s behaviour and state can strengthen (positive feedback) or weaken (negative feedback) individual differences when experiences such as predator encounters or winning contests are dependent on behavioural type. We examined the influence of foraging on individual-level consistency in refuge use (a measure of risk-taking, i.e. boldness) in three-spined sticklebacks, Gasterosteus aculeatus, and particularly whether changes in refuge use depended on boldness measured under control conditions. In the control treatment trials with no food, individuals were repeatable in refuge use across repeated trials, and this behavioural consistency did not differ between the start and end of these trials. In contrast, when food was available, individuals showed a higher degree of consistency in refuge use at the start of the trials versus controls but this consistency significantly reduced by the end of the trials. The effect of the opportunity to forage was dependent on behavioural type, with bolder fish varying more in their refuge use between the start and the end of the feeding trials than shyer fish, and boldness positively predicted the likelihood of feeding at the start but not at the end of the trials. This suggests a state-behaviour feedback, but there was no overall trend in how bolder individuals changed their behaviour. Our study shows that personality variation can be suppressed in foraging contexts and a potential but unpredictable role of feedbacks between state and behaviour. Significance statement In this experimental study, we examined how foraging influences consistency in risk-taking in individual three-spined sticklebacks. We show that bolder individuals become less consistent in their risk-taking behaviour than shyer individuals during foraging. Some bolder individuals reinforce their risk-taking behaviour, suggesting a positive feedback between state and behaviour, while others converge on the behaviour of shyer individuals, suggesting a negative feedback. In support of a role of satiation in driving negative feedback effects, we found that bolder individuals were more likely to feed at the start but not at the end of the trials. Overall, our findings suggest that foraging can influence personality variation in risk-taking behaviour; however, the role of feedbacks may be unpredictable.

Sign in / Sign up

Export Citation Format

Share Document