Chapter 9 Demography and dynamics of hard clam populations

Fegley, Stephen R.

doi:10.1016/s0167-9309(01)80037-5

Cited by 20 publications

(33 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In each location, four replicate 5 ft 3 5 ft (1.52 m 3 1.52 m) plots of each strain were planted at a density of 50 clams ) (1,250 clams per plot, 5,000 per strain, 25,000 per location). These densities are similar to those used by commercial operations, but are considerably higher than most reported natural population densities (Fegley 2001). Replicate plots were distributed according to a randomized block design.…”

Section: Initial Planting and Grow-out Of Seedmentioning

confidence: 76%

Influence of Host Genetic Origin and Geographic Location on QPX Disease in Northern Quahogs (=hard Clams), Mercenaria Mercenaria

Calvo

Ford

Kraeuter

et al. 2007

Journal of Shellfish Research

View full text Add to dashboard Cite

QPX (Quahog Parasite Unknown) a protistan pathogen of northern quahogs (=hard clams), Mercenaria mercenaria, has caused disease outbreaks in maritime Canada, and in Massachusetts, New York, New Jersey, and Virginia, USA. Although epizootics have occurred in wild hard clam populations, the parasite has most seriously affected cultured hard clams, suggesting that aquaculture practices may promote or predispose clams to the disease. In this investigation the influence of clam genetic origin and the geographic location at where they are grown on QPX disease susceptibility was examined in a common garden experiment. Aquaculture stocks were acquired from hatcheries in Massachusetts, New Jersey, Virginia, South Carolina, and Florida and spawned at a single hatchery in Virginia. All stocks were originally, although not exclusively, derived from wild hard clam populations from each state. The seed clams were deployed at two sites, New Jersey and Virginia, and evaluated during the subsequent 2.5 y for growth, survival, and QPX disease. At both sites, South Carolina-and Florida-derived clam stocks exhibited significantly higher QPX prevalence and lower survival than New Jersey and Massachusetts clam stocks. Levels in the Virginia stock were intermediate. In Virginia, mortality at the termination of the experiment was 78%, 52%, 36%, 33%, and 20% in the Florida, South Carolina, Virginia, Massachusetts, and New Jersey hard clam stocks, respectively. Mortality was significantly correlated with QPX prevalence. Maximum QPX prevalence in the South Carolina and Florida stocks ranged from 19% to 21% and 27% to 29%, respectively, whereas in the Virginia, New Jersey, and Massachusetts stocks prevalence was 10% or less. Similar trends were observed in New Jersey where mortality at the termination of the experiment was estimated to be 53%, 40%, 20%, 6%, and 4% in the Florida, South Carolina, Virginia, Massachusetts, and New Jersey clam stocks, respectively. QPX prevalence peaked at 18% in the Florida stock, 38% in the South Carolina, 18% in the Virginia, and 5% in the New Jersey and Massachusetts stocks. These results suggest that host genotype is an important determinant in susceptibility to QPX disease. As such, hard clam culturist should consider the genetic origin of clam seed stocks an important component of their QPX disease avoidance/management strategies.

show abstract

Section: Initial Planting and Grow-out Of Seedmentioning

confidence: 76%

Influence of Host Genetic Origin and Geographic Location on QPX Disease in Northern Quahogs (=hard Clams), Mercenaria Mercenaria

Calvo

Ford

Kraeuter

et al. 2007

Journal of Shellfish Research

View full text Add to dashboard Cite

show abstract

“…we apply commonly used fisheries statistics that help to evaluate and manage living hard clam populations by quantifying their size classes, survivorship, and ontogenetic age (Fegley, 2001). In so doing we are able to assess relative harvesting pressure during the Archaic period on St. catherines Island and at cannon's Point.…”

Section: Discussionmentioning

confidence: 99%

“…we follow the methods of Quitmyer, Jones, and Arnold (1997) (walker and tenore, 1984;Fegley, 2001). the specimens were transported to the St. catherines Island compound where they were quickly frozen in a commercial grade freezer.…”

Section: Discussionmentioning

confidence: 99%

Untitled

Reitz¹,

Quitmyer²,

Thomas³

et al. 2012

Anthropol. Pap. Am. Mus. Nat. Hist.

View full text Add to dashboard Cite

“…Differences between the age-frequency distribution observed in the Southampton Water population and those in other study areas indicate that Southampton Water is a marginal habitat for the species (Fegley, 2001). Poor recruitment observed (Richardson & Walker, 1991) may result from large numbers of animals removed by the fishery and damage to the physical environment (Eno et al, 1997), and/or from adverse environmental conditions, e.g.…”

Section: Introductionmentioning

confidence: 95%

“…temperature effects (Loosanoff et al, 1951;Loosanoff, 1959). The status of introduced populations in The Netherlands, Belgium and on the west coast of France is unknown (Fegley, 2001). Data on the physiological ecology of M. mercenaria, including metabolic rate and growth across the original North American biogeographical range, have been reviewed by Grizzle et al (2001).…”

Section: Introductionmentioning

confidence: 99%

Metabolic rate and growth in the temperate bivalve Mercenaria mercenaria at a biogeographical limit, from the English Channel

2010

View full text Add to dashboard Cite

Metabolism and growth rate of the hard clam, Mercenaria mercenaria, were investigated in a population invasive to Southampton Water, southern England. An individual metabolic model expressed as a function of soft tissue dry mass was fitted to data of 18 individuals (log (VO 2 ) ¼ 2 1.952 þ 0.543 † log (DM); F 1,16 ¼ 201.18, P , 0.001, r 2 ¼ 0.926). A von Bertalanffy growth function was fitted to 227 size-at-age data pairs of 18 individuals (H t ¼ 80.13 † (1 2 e 20.149 † (t 2 0.542) ); r 2 ¼ 0.927). Individual age-specific somatic production was calculated, demonstrating increase with age to a maximum of 3.88 kJ y 21 at ten years old followed by decrease, and individual age-specific annual respiration was calculated, demonstrating asymptotic increase with age to 231.37 kJ y 21 at 30 years old. Results found here lie within the physiological tolerances reported across the biogeographical range, suggesting that the species' biogeographical limitation in the UK to Southampton Water results from ecological rather than physiological factors.

show abstract

Chapter 9 Demography and dynamics of hard clam populations

Cited by 20 publications

References 44 publications

Influence of Host Genetic Origin and Geographic Location on QPX Disease in Northern Quahogs (=hard Clams), Mercenaria Mercenaria

Influence of Host Genetic Origin and Geographic Location on QPX Disease in Northern Quahogs (=hard Clams), Mercenaria Mercenaria

Untitled

Metabolic rate and growth in the temperate bivalve Mercenaria mercenaria at a biogeographical limit, from the English Channel

Contact Info

Product

Resources

About