scholarly journals Space use and its effects on reproductive success of anadromous Atlantic salmon

2016 ◽  
Vol 73 (10) ◽  
pp. 1461-1471 ◽  
Author(s):  
Cédric Tentelier ◽  
Nicolas Larranaga ◽  
Olivier Lepais ◽  
Aurélie Manicki ◽  
Jacques Rives ◽  
...  
Keyword(s):  
Reproductive Success ◽  
Atlantic Salmon ◽  
Home Range ◽  
Space Use ◽  
Parentage Analysis ◽  
First Year ◽  
Radio Tracking ◽  
Female Reproductive Success ◽  
Second Year ◽  
Individual Features

We combined habitat mapping, radio tracking of adults, redd mapping, and genetic parentage analysis on juveniles for 2 consecutive years to test eight predictions on the reproductive payoffs and individual features associated with space use tactics of anadromous Atlantic salmon (Salmo salar) in a natural population. Regarding payoffs, we found that (1) males settled in better habitat, visited more redds, and tended to get more mates than males settled in poorer habitat; (2) they also sired more offspring; (3) the latter effect was stronger in the first year, when redds were more aggregated; and (4) female reproductive success increased with habitat quality in their home range, especially in the first year. For individual features, (5) individuals that settled earlier in their home range had better habitat for juvenile production, but only in the first year; (6) females were less mobile than males, especially in the second year; (7) larger males did not settle in better habitats than smaller males; and (8) smaller males were not more mobile than larger males.

The effect of multiple mating on female reproductive success in the simultaneously hermaphroditic land snail Arianta arbustorum

1993 ◽  
Vol 71 (12) ◽  
pp. 2431-2436 ◽  
Author(s):  
Xiaofeng Chen ◽  
Bruno Baur
Keyword(s):  
Reproductive Success ◽  
Hatching Success ◽  
Multiple Mating ◽  
Reproductive Traits ◽  
Land Snail ◽  
First Year ◽  
Female Reproductive Success ◽  
Female Function ◽  
Arianta Arbustorum ◽  
Second Year

The simultaneously hermaphroditic land snail Arianta arbustorum mates several times in the course of a reproductive season. Repeated matings might be adaptive for the male function of A. arbustorum to inseminate several "females." We designed an experiment to evaluate the effects of repeated mating on the female reproductive success of this hermaphrodite. Reproductive traits and survival were examined over 2 years in individuals that copulated several times per year (snails were kept in pairs), in individuals that copulated twice (once at the beginning of each year) or once (at the beginning of the first year only), and in individuals prevented from copulating (they were kept isolated). Copulations were not always reciprocally successful: 3 of 57 snails (5.3%) failed to produce fertile eggs, although their mates reproduced successfully. Similarly, 2 of 15 pairs (13.3%) failed to reproduce successfully. Snails allowed to mate repeatedly within each season tended to lay more eggs than snails that mated once per year. However, the numbers of hatchlings did not differ significantly between the two treatment groups, because eggs laid by snails allowed to mate repeatedly had a lower hatching success. Snails that remated in the second year laid more eggs that had higher hatching success, and thus produced more hatchlings than snails that mated once at the beginning of the first year only. Snails that were prevented from mating produced a few hatchlings (by self-fertilization) in the second year; their reproductive success was less than 1% of that of mated snails. Our results suggest that multiple mating is also adaptive for the female function of A. arbustorum by increasing female fecundity and fertility and serving as a hedge against unsuccessful copulations.

scholarly journals Lifetime reproductive success of Greylag Geese Anser anser breeding in south Sweden

Ornis Svecica ◽  
2018 ◽  
Vol 28 (1) ◽  
Author(s):  
Leif Nilsson ◽  
Hakon Kampe-Persson
Keyword(s):  
Reproductive Success ◽  
Life Time ◽  
Breeding Population ◽  
Lifetime Reproductive Success ◽  
First Year ◽  
Anser Anser ◽  
South West ◽  
South Sweden ◽  
Second Year ◽  
Greylag Geese

During 1984–2009, 664 adults and 1,944 goslings of Greylag Geese Anser anser were neck-banded in south-west Scania, Sweden. After hatching the area was carefully searched for marked geese, giving more than 100,000 re-sightings. Of those marked as goslings 71% survived the first year, 52% the second year, and the oldest bird recorded was 25 years. About 50% of the survivors were recruited into the breeding population when two to three years old. Of 1,187 geese that survived for at least two years, 25% produced at least one brood of small young, and 18% at least one fledged young. The maximum life-time number of broods with fledged young was nine, but 50% of the geese known to have bred successfully produced only one brood of fledged young. Ten percent of the geese seen with small goslings produced 47% of all fledged young. The maximum number of fledged young for a goose of known age was 32 (age 15 years), but two geese marked as adults and followed for 16 and 17 years produced 40 fledglings each.

Dispersal of subadult moose (Alces alces) in a nonmigratory population

1992 ◽  
Vol 70 (7) ◽  
pp. 1309-1314 ◽  
Author(s):  
Göran N. Cederlund ◽  
Håkan K. G. Sand
Keyword(s):  
Home Range ◽  
Alces Alces ◽  
First Year ◽  
Home Ranges ◽  
Radio Tracking ◽  
Sedentary Population ◽  
Linear Distance ◽  
Demographic Processes ◽  
Range Overlap ◽  
Demographic Features

Dispersal of subadult moose (Alces alces) in a sedentary population in central Sweden was studied during 1983 – 1989 by radio-tracking individuals for up to 11 seasons after their abandonment by the cow. Linear distance between geometric centers of natal area and consecutive home ranges increased with time among males, but not by more than about 4 km. The main increase occurred in autumn, probably due to rutting activities. Females maintained a fairly consistent distance of approximately 1 km throughout the study period. Seasonal home range overlap of natal area was negatively correlated with time for both sexes, but the patterns in the decrease differed. For males, the overlap was 10–40% after the first year, whereas female home ranges never overlapped by less than 40%. Overlap of consecutive seasonal home ranges increased significantly with age in both sexes. Neither sex dispersed out of the study area, since the animals were highly philopatric. The absence of dispersal (high philopatry) in moose in Fennoscandia is an important factor affecting demographic processes (and perhaps also genetic processes) within and between populations. It is important to distinguish different subpopulations of moose and manage them with respect to their unique demographic features.

scholarly journals Home ground advantage: Local Atlantic salmon have higher reproductive fitness than dispersers in the wild

2019 ◽  
Vol 5 (2) ◽  
pp. eaav1112 ◽  
Author(s):  
Kenyon B. Mobley ◽  
Hanna Granroth-Wilding ◽  
Mikko Ellmen ◽  
Juha-Pekka Vähä ◽  
Tutku Aykanat ◽  
...  
Keyword(s):  
Reproductive Success ◽  
Atlantic Salmon ◽  
Local Adaptation ◽  
Spatial Scales ◽  
Juvenile Fish ◽  
Natural Populations ◽  
Parentage Analysis ◽  
Population Divergence ◽  
Natal Habitat ◽  
In The Wild

A long-held, but poorly tested, assumption in natural populations is that individuals that disperse into new areas for reproduction are at a disadvantage compared to individuals that reproduce in their natal habitat, underpinning the eco-evolutionary processes of local adaptation and ecological speciation. Here, we capitalize on fine-scale population structure and natural dispersal events to compare the reproductive success of local and dispersing individuals captured on the same spawning ground in four consecutive parent-offspring cohorts of wild Atlantic salmon (Salmo salar). Parentage analysis conducted on adults and juvenile fish showed that local females and males had 9.6 and 2.9 times higher reproductive success than dispersers, respectively. Our results reveal how higher reproductive success in local spawners compared to dispersers may act in natural populations to drive population divergence and promote local adaptation over microgeographic spatial scales without clear morphological differences between populations.

Stream Studies on Planted Atlantic Salmon

1954 ◽  
Vol 11 (4) ◽  
pp. 362-403 ◽  
Author(s):  
H. R. McCrimmon
Keyword(s):  
Atlantic Salmon ◽  
Population Studies ◽  
First Year ◽  
Salmon Fry ◽  
Average Survival ◽  
Summer Temperatures ◽  
Second Year ◽  
Made In

Plantings of Atlantic salmon fry were made in the Duffin Creek system in order to determine the survival and distribution of salmon under a variety of stream conditions. Population studies estimated that the three general June plantings resulted in an average survival of 12.7 per cent until the autumn of the first year, 9.2 per cent until the autumn of the second year. High summer temperatures were lethal to the salmon in certain parts of the creek system. Over the balance of the planted part, the greatest mortality occurred soon after plantings when heavy predation by other species of fish occurred. The extent of predation was determined largely by the amount of shelter available to the fry. Suitable shelter for the young salmon was limited generally to gravelly riffle areas where the degree of bottom sedimentation determined the amount of shelter offered. Other stream conditions were of minor or no importance in salmon survival. Further losses of salmon were low once the young salmon had become established in the creek system.

scholarly journals Home ground advantage: selection against dispersers promotes local adaptation in wild Atlantic salmon

2018 ◽  
Author(s):  
Kenyon B. Mobley ◽  
Hanna Granroth-Wilding ◽  
Mikko Ellmen ◽  
Juha-Pekka Vähä ◽  
Tutku Aykanat ◽  
...  
Keyword(s):  
Reproductive Success ◽  
Atlantic Salmon ◽  
Local Adaptation ◽  
Spatial Scales ◽  
Juvenile Fish ◽  
Natural Populations ◽  
Parentage Analysis ◽  
Population Divergence ◽  
Natal Habitat ◽  
Scale Population

AbstractA long-held, but poorly tested, assumption in natural populations is that individuals that disperse into new areas for reproduction are at a disadvantage compared to individuals that reproduce in their natal habitat, underpinning the eco-evolutionary processes of local adaptation and ecological speciation. Here, we capitalize on fine-scale population structure and natural dispersal events to compare the reproductive success of local and dispersing individuals captured on the same spawning ground in four consecutive parent-offspring cohorts of wild Atlantic salmon (Salmo salar). Parentage analysis conducted on adults and juvenile fish showed that local females and males had 9.6 and 2.9 times higher reproductive success than dispersers, respectively. Our results reveal how dispersal disadvantage in reproductive success may act in natural populations to drive population divergence and local adaptation over microgeographic spatial scales without clear morphological differences or physical barriers to gene flow.

An inevitable crisis? From first to second year in counsellor training

2020 ◽  
Vol 5 (1) ◽  
pp. 74-89
Author(s):  
Hugh Crago
Keyword(s):  
Right Hemisphere ◽  
Training Programme ◽  
First Year ◽  
Training Experience ◽  
Counsellor Training ◽  
Student Dropout ◽  
Second Year ◽  
Neurological Research ◽  
First Year Of Life ◽  
And Control

In a seminal 1973 paper, Robert Clark described the very different “cultures” of the first and second year students in a four year clinical psychology PhD programme. The author applies Clark’s template to his own experiences as trainee or trainer in five different counsellor education programmes, one in the US and four in Australia. Each of the programmes, to varying degrees, demonstrates key features of the pattern identified by Clark, where the first year is “therapeutic” and other-oriented, the second is “professional” and self-focused. The author concludes that all the surveyed programmes exhibited some level of “second year crisis”, in which a significant number of students felt abandoned, dissatisfied, or rebellious. The author extends and refines Clark’s developmental analogy (first year = childhood; second year = adolescence) to reflect recent neurological research, in particular, the shift from a right hemisphere-dominant first year of life, prioritising affiliative needs, to a left hemisphere-dominant second year, prioritising autonomy and control. This shift is paralleled later by a more gradual move from a protective, supportive childhood to necessary, but sometimes conflictual, individuation in adolescence. The first two years of a counsellor training programme broadly echo this process, a process exacerbated by the second year internship/placement, in which students must “leave home” and adjust to unfamiliar, potentially less nurturing, authority figures. Finally, the author suggests introducing more rigorous “academic holding” into the first year, and greater attention to “therapeutic holding” of dissident students in the second, hopefully decreasing student dropout, and achieving a better balanced training experience.

Implementation of the Second-year course in an Engineering Professional Spine

2018 ◽  
Author(s):  
Umar Iqbal ◽  
Deena Salem ◽  
David Strong
Keyword(s):  
Learning Outcomes ◽  
Research University ◽  
Engineering Students ◽  
Employability Skills ◽  
First Year ◽  
Computer Engineering ◽  
Core Courses ◽  
Second Year ◽  
First Time ◽  
Academic Year

The objective of this paper is to document the experience of developing and implementing a second-year course in an engineering professional spine that was developed in a first-tier research university and relies on project-based core courses. The main objective of this spine is to develop the students’ cognitive and employability skills that will allow them to stand out from the crowd of other engineering graduates.The spine was developed and delivered for the first time in the academic year 2010-2011 for first-year general engineering students. In the year 2011-2012, those students joined different programs, and accordingly the second-year course was tailored to align with the different programs’ learning outcomes. This paper discusses the development and implementation of the course in the Electrical and Computer Engineering (ECE) department.

Exploring the Implementation of Early Math Assessments in Kindergarten Classrooms: A Research-Practice Collaboration

2020 ◽  
Author(s):  
Jennifer McDonald ◽  
Rebecca Merkley ◽  
Jacqueline Mickle ◽  
Lisa Collimore ◽  
Daniel Ansari
Keyword(s):  
Mathematical Thinking ◽  
Math Education ◽  
Kindergarten Students ◽  
First Year ◽  
Research Practice ◽  
Early Numeracy ◽  
Future Directions ◽  
Collaborative Project ◽  
Practice Gap ◽  
Second Year

Research in cognitive development has highlighted that early numeracy skills are associated with later math achievement, suggesting that these skills should be targeted in early math education. Here we tested whether tools used by researchers to assess mathematical thinking could be useful in the classroom. This paper describes a collaborative project between cognitive scientists and school board researchers/educators implementing numeracy screeners with kindergarten students over the course of three school years. The Give-A-Number task (Wynn, 1990) was used with first-year kindergarten students and the Numeracy Screener [BLINDED] with second-year kindergarten students. Results indicated that educators (N = 59) found the tools feasible to implement and helpful for exploring their students’ thinking and targeting instruction. The Educators’ feedback also helped inform improvements to the implementation of the tools and future directions for both the schools and the researchers. This work emphasizes the importance of transdisciplinary collaboration to address the research-practice gap.

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