The Effect of the Chemical Composition of Low Salinity Water on the Growth, Development, and Survival of Cultured Juvenile Blue Crabs

<p>Cultured juvenile blue crabs ( Callinectes sapidus Rathbun) were held for up to 77 days and monitored for survival, growth and development in low salinity water containing various compositions of ions. ~rabs were isolated in separate containers and placed in thirty gallon aquaria containing 2ppt of ion solution. Temperature, ambient, humidity, and nitrite levels were monitored daily. Molts were measured to determine growth, and molt increments were recorded to determine rate of development. The first part of the study compared ratios of sodium chloride (NaCl) to commercial sea salt (SS) in five treatments: 100% NaCl, 100% SS, 25:75 NaCl/SS, 50:50 NaCl/SS, and 75:25 NaCl/SS. The second par! of the study examined mixed ion treatments in water containing solutions of NaCl; NaCl and calcium chloride (CaCl₂); NaCl, CaCl₂, and magnesium chloride(MgCl₂); NaCl, MgCl₂, CaCl₂, and potassium Chloride 9KCl); and SS. Another set of treatments examined the addition of magnesium sulfate (MgSO₄) to the mixed ion solutions. The results of these experiments indicate that acceptable yields of cultured blue crabs (>50% survival) can be achieved in solutions of up to 50% NaCl mixed with commercial sea salt. Mixed ion solutions containing NaCl, MgCl₂, CaCl₂, and KCl, with or without the presence of MgSO₄, initially facilitated survival, growth and development, but delayed growth and development followed by unacceptably high mortality occurred within 12-42 days. A limiting ion or ions has yet to be identified for acceptable survival of juvenile blue crabs in a mixed ion solution.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Masters Thesis

Discipline thesis:degree_discipline

Coastal Sciences, Gulf Coast Research Laboratory

Year dc:date.available

2011

Author dc:creator

• Gibson, Dyan Patricia

Contributors dc:contributor

• Richard Fulford
• James Franks
• Bruce Comyns

Repository record dc:identifier

https://aquila.usm.edu/masters_theses/482

OAI identifier oai:identifier

oai:aquila.usm.edu:masters_theses-1554