scholarly journals Young-of-the-year recruitment does not predict the abundance of older age classes in black rockfish in Barkley Sound, British Columbia, Canada

2017 ◽  
Vol 574 ◽  
pp. 113-126 ◽  
Author(s):  
DR Haggarty ◽  
KE Lotterhos ◽  
JB Shurin
Keyword(s):  
British Columbia ◽  
Older Age ◽  
Age Classes ◽  
Black Rockfish ◽  
Barkley Sound ◽  
Young Of The Year

scholarly journals Young-of-the-year recruitment does not predict the abundance of older age classes in black rockfish in Barkley Sound, British Columbia, Canada

2018 ◽  
Author(s):  
Dana Haggarty ◽  
Katie E. Lotterhos ◽  
Jonathan B. Shurin
Keyword(s):  
Marine Reserve ◽  
Spatiotemporal Variability ◽  
Suitable Habitat ◽  
Conservation Area ◽  
Black Rockfish ◽  
Barkley Sound ◽  
Class Strength ◽  
Young Of The Year ◽  
Sebastes Melanops ◽  
Yoy Fish

Recruitment and connectivity are important criteria for designing effective marine protected areas, as coastal fish populations must be sustained by settling juveniles. However, patterns of recruitment are difficult to observe, and adults and juveniles may occupy distinct habitats. We examined patterns of adult black rockfish Sebastes melanops abundance with respect to habitat and spatiotemporal variability in recruitment of young-of-the-year (YOY) to determine how these variables influence population density in and around a rockfish conservation area (RCA). For most year classes, there was no relationship between the density of YOY and the density of 1 yr olds or the density of adults, and instead habitat variables such as topological complexity and the amount of rocky substrate predicted adult black rockfish abundance. For 1 year class of moderate abundance at the YOY stage but high abundance at the 1 yr old stage, a significant relationship between 1 yr olds and subsequent adults was observed. We surmise that overwinter survival of YOY fish may be an important determinant for year-class strength in black rockfish. Although a companion study found low recruitment of YOY inside the RCA, our data indicate that the density of many species of rockfish was higher inside the RCA. These results highlight how the density of adults can be determined by post-recruitment processes such as movement into suitable habitat and mortality, rather than by recruitment of YOY, and have implications for the design of marine reserve networks.

scholarly journals Zika: an ongoing threat to women and infants

2018 ◽  
Vol 34 (11) ◽  
Author(s):  
Beatriz Macedo Coimbra dos Santos ◽  
Flavio Codeço Coelho ◽  
Margaret Armstrong ◽  
Valeria Saraceni ◽  
Cristina Lemos
Keyword(s):  
Sexual Transmission ◽  
Risk Groups ◽  
Gender Disparity ◽  
Incidence Rates ◽  
Older Age ◽  
Age Classes ◽  
Sharp Drop ◽  
Men And Women ◽  
Women And Children ◽  
Previous Summer

Recent data from the municipality of Rio de Janeiro, Brazil, shows a sharp drop in the number of reported occurrences of Zika during the summer of 2016/2017, compared to the previous summer. There is still a much higher incidence among women than men, almost certainly due to sexual transmission. An unexpected feature of the new data is that there are proportionally far more cases affecting children under 15 months than older age classes. By comparing incidence rates in 2016/2017 and 2015/2016, we were able to deduce the proportion of reported cases affecting men and women, and verify that gender disparity is still present. Women and children are still risk groups for Zika infection, even during non-epidemic seasons.

Biology, Management, and Protection of North American Sturgeon

2002 ◽  
Keyword(s):  
Population Growth ◽  
Life Histories ◽  
Habitat Restoration ◽  
Negative Impact ◽  
Elasticity Analysis ◽  
Age Classes ◽  
Adult Age ◽  
Significant Negative Impact ◽  
Young Of The Year ◽  
Restoration Strategies

Abstract.— We use elasticity analyses for three sturgeon species, the shortnose sturgeon <em>Acipenser brevirostrum</em>, Atlantic sturgeon <em>A. oxyrinchus</em>, and white sturgeon <em>A. transmontanus</em>, to calculate the potential to increase population growth rate, λ, by improving survival and fecundity. Elasticity analysis is a means of assessing changes to λ resulting from conservation initiatives. The elasticity of λ to survival has a characteristic profile that includes a plateau of high elasticity values across the young of the year and the juvenile ages. However, survival elasticity falls at maturity and declines rapidly with increasing adult age. Changes to fecundity have relatively little impact; the total of the fecundity elasticities over all ages is equal to the single young-of-the-year survival elasticity. Even though the young-of-the-year survival elasticity is equal to that of any other juvenile age, the overall opportunity for affecting λ; is strongest in the young-of-the-year age-class because of its exceptional potential for increase to survival. The juvenile and adult stages have roughly equal total survival elasticities. These findings are particularly relevant in understanding the contributions of hatcheries, harvest regulations and habitat restoration as strategies for sturgeon conservation. Hatcheries are focused on the young of the year, the demographically most sensitive component of sturgeon life histories, and thus have the potential to make significant increases to λ if the genetic, evolutionary and ecological impacts of hatcheries can be controlled. Harvest, even at low levels, can have a significant negative impact on λ when it affects multiple age classes. Managers can use elasticity analysis to calculate the total impact of harvest and to mathematically evaluate the trade-off in exploiting young versus older individuals. Habitat restoration strategies, usually assessed in terms of survivals of the age classes impacted, would also benefit from using elasticity analysis to interpret their contributions to l. If restoration efforts target the survival of age classes with high elasticities, significant population growth may be achieved.

First Records of the Striped Bass, Morone saxatilis, in British Columbia Waters

1972 ◽  
Vol 29 (3) ◽  
pp. 337-339 ◽  
Author(s):  
C. R. Forrester ◽  
Alex E. Peden ◽  
R. M. Wilson
Keyword(s):  
British Columbia ◽  
Striped Bass ◽  
Pacific Coast ◽  
Puget Sound ◽  
Morone Saxatilis ◽  
San Juan ◽  
Barkley Sound ◽  
The Pacific

Two specimens of the striped bass (Morone saxatilis) were taken in British Columbia waters in 1971. One was taken off Port San Juan (48°30′N, 124°30′W) and one in Barkley Sound (48°58′N, 125°03′W). Previous most northerly published record for the Pacific coast was from Puget Sound, Washington.

Microsatellite identification of individual sockeye salmon in Barkley Sound, British Columbia

2002 ◽  
Vol 61 (4) ◽  
pp. 1021-1032 ◽  
Author(s):  
T. D. Beacham ◽  
B. McIntosh ◽  
C. MacConnachie
Keyword(s):  
British Columbia ◽  
Sockeye Salmon ◽  
Barkley Sound

RECORDS OF DECAPOD CRUSTACEA FROM BRITISH COLUMBIA

1961 ◽  
Vol 39 (1) ◽  
pp. 59-62 ◽  
Author(s):  
T. H. Butler
Keyword(s):  
British Columbia ◽  
New Record ◽  
Barkley Sound ◽  
Decapod Crustacea

Axiopsis spinulicauda was taken in Holberg Inlet and Barkley Sound at 50 to 70 fathoms, and is a new record for British Columbia. The typically oceanic Eualus macrophthalmus was taken in Howe Sound at 60 to 75 fathoms and Lopholithodes foraminatus at localities north to Hecate Strait. Cancer gracilis was found in deeper water (74 to 78 fathoms) than heretofore and C. magister, at 58 to 98 fathoms.

scholarly journals Zika: An ongoing threat to women and infants

2017 ◽  
Author(s):  
Beatriz Macedo Coimbra ◽  
Flávio Codeço Coelho ◽  
Margaret Armstrong ◽  
Valeria Saraceni ◽  
Cristina Lemos
Keyword(s):  
Sexual Transmission ◽  
Herd Immunity ◽  
Risk Groups ◽  
Older Age ◽  
Age Classes ◽  
Sharp Drop ◽  
Men And Women ◽  
Epidemic Season ◽  
Women And Children ◽  
Previous Summer

AbstractRecent data from Rio de Janeiro shows a sharp drop in the number of notified cases of Zika in the summer of 2016-17, compared to the previous summer. This is probably due to herd immunity built up after the previous year's epidemic. There is still a much higher incidence among women than men, almost certainly due to sexual transmission. An unexpected feature of the new data is that there are proportionally far more cases in children under 15 months than in older age classes. By comparing the incidence for 2016-17 with that of 2015-16, we can deduce the proportion of reported cases for men and women, and also verify that the disparity of incidence between them is still present. Women and children still represent risk groups with regard to Zika infection, even during a non-epidemic season.

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