Edgerton Research Laboratory

Boston, MA, United States

Edgerton Research Laboratory

Boston, MA, United States
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Fortune S.M.E.,University of British Columbia | Trites A.W.,University of British Columbia | Perryman W.L.,Southwest Fisheries Science Center | Moore M.J.,Woods Hole Oceanographic Institution | And 2 more authors.
Journal of Mammalogy | Year: 2012

Body growth of North Atlantic right whales (Eubalaena glacialis) was described from measurements of known-age live and dead individuals to gain insights into the nutritional needs and life-history strategies of this endangered species. Body lengths from 154 individuals revealed that calves more than doubled in size and attained three-fourths of asymptotic adult size by the time they had weaned at 12 months. Calves gained on average ∼1.7 cm and ∼34 kg per day while nursing during this extremely rapid growth phase. Mean predicted lengths and body mass were 4.2 m and 1.1 metric tons (mt) at birth, 10.3 m and 13.5 mt at weaning, and 13.6 m and 29.6 mt when fully grown. Growth of right whales was best described using a 2-phased Gompertz growth model and could not be fit using any of the single continuous growth models commonly used for other mammals. Rapid growth during dependency may minimize the risk of predation and maximize calf survival. Rapid calf growth also may maximize development of the mouth and baleen to optimize foraging efficiency of juveniles at the time of weaning, as well as improve reproductive fitness by reducing the age at which sexual maturity is attained. However, transferring the amount of energy needed to support the rapid postnatal growth of North Atlantic right whales may ultimately affect the intervals between pregnancies (>3 years) of mature females. © 2012 American Society of Mammalogists.

Gallagher A.J.,Northeastern University | Frick L.H.,Monash University | Bushnell P.G.,Indiana University at South Bend | Brill R.W.,Virginia Institute of Marine Science | And 2 more authors.
Journal of Aquatic Animal Health | Year: 2010

Blood gas, pH, and lactate data are often used to assess the physiological status and health of fish and can often be most valuable when blood samples are analyzed immediately after collection. Portable clinical analyzers allow these measurements to be made easily in the field. However, these instruments are designed for clinical use and thus process samples at 37°C. A few studies have validated the use of portable clinical analyzers for assessing blood gases and acid-base profiles in teleosts, but equivalent data are not available for elasmobranchs. We therefore examined the relationship of blood gas, pH, and lactate values measured with an i-STAT portable clinical analyzer with those measured using standard laboratory blood gas (thermostatted to 25°C) and lactate analyzers in samples taken from three species of carcharhiniform sharks. We found tight correlations (r2.0.90) between these methods for pH, pO2, pCO2, and lactate level values. We thus developed species-specific equations for converting blood values measured with an i-STAT portable clinical analyzer to those taken at 25°C. Additional studies need to address a wider range of temperatures and elasmobranch species. © Copyright by the American Fisheries Society 2010.

Storai T.,Centro Of Educazione Ambientale E Alla Sostenibilita Laguna Of Nora | Zinzula L.,Centro Of Educazione Ambientale E Alla Sostenibilita Laguna Of Nora | Repetto S.,Localita Piana Nord | Zuffa M.,Museo L. Donini | And 2 more authors.
Fisheries Research | Year: 2011

The species composition and extent of large elasmobranch bycatch in the Sardinian tuna trap fisheries have received minimal attention in the primary literature. The Sardinian Large Elasmobranch Database (SLED), a non-governmental project, contains records from direct observations, fishing industry sources and reviews from the literature regarding the extent and composition of large elasmobranch bycatch from the only six tuna traps at six fishing sites (Saline; Capo Testa; Carloforte; Portoscuso; Calasetta; and Portopaglia) from the period of 1990 to 2009. During this time period, 42 bycatch events were documented that were comprised of the incidental capture of 15 Mobulid rays and 27 large sharks representing ten species and seven families (23% of the total elasmobranch species previously reported in Sardinian waters). Even though the low number of collective elasmobranchs captured (n= 42) in this study does not pose a conservation concern several bycatch species considered rare and/or depleted in this region were among the species observed. Mobula mobular was the most abundant elasmobranch species caught, with Alopias vulpinus the most commonly caught shark species. There were differences in the catch per unit effort between the six sites with the highest CPUE occurring in Saline, Carloforte and Porto Paglia. Although the sheer volume and conservation impact of traditional tuna traps on large elasmobranchs is exceeded by other fishing gears in Mediterranean waters, small scale (long term) bycatch monitoring programs are vital when evaluating the presence, biodiversity and conservation of elasmobranchs in previously unstudied areas. © 2011 Elsevier B.V.

Laubenheimer H.,University of Saint Úrsula | Rhyne A.L.,Roger Williams University | Rhyne A.L.,Edgerton Research Laboratory
Zootaxa | Year: 2010

A new peppermint shrimp species, Lysmata rauli sp. nov., is described based on a specimen collected in shallow subtidal waters off Salvador, Bahia, Brazil. Lysmata rauli sp. nov. was identified from fresh material collected in tide pools. L. rauli sp. nov. appears to be rare in the region with only two specimens collected from Salvador, Brazil. The new species can be readily distinguished from all other species by the absences of a well developed accessory branch, number of carpal segments of the second pereiopod, presence of a well developed pterygostomial tooth and number of teeth on the rostrum, as well as by color pattern. Copyright © 2010 Magnolia Press.

Fiedler G.C.,University of Maryland University College | Rhyne A.L.,Edgerton Research Laboratory | Rhyne A.L.,Roger Williams University | Segawa R.,Tokyo Metroplitan University | And 2 more authors.
BMC Evolutionary Biology | Year: 2010

Background. The hippolytid genus Lysmata is characterized by simultaneous hermaphroditism, a very rare sexual system among Decapoda. Specialized cleaning behavior is reported in a few pair-living species; these life history traits vary within the genus. Unfortunately, the systematics of Lysmata and the Hippolytidae itself are in contention, making it difficult to examine these taxa for trends in life history traits. A phylogeny of Lysmata and related taxa is needed, to clarify their evolutionary relationships and the origin of their unique sexual pattern. In this study, we present a molecular phylogenetic analysis among species of Lysmata, related genera, and several putative hippolytids. The analysis is based upon DNA sequences of two genes, 16S mtDNA and nuclear 28S rRNA. Phylogenetic trees were estimated using Bayesian Inference, Maximum Likelihood, and Maximum Parsimony. Results. Phylogenetic analysis of 29 species of Lysmata, eight genera of Hippolytidae and two genera of Barbouriidae based on a single (16S, 28S) and combined gene approach (16S+28S) indicates that three groups of Lysmata differentiate according to antennular morphology: (1) Lysmata, having a multi-segmented accessory branch, (2) Hippolysmata (prior to Chace 1972), with a one-segmented accessory branch, and (3) a third group of Lysmata outliers, with one-segmented unguiform accessory branch, and close affinity to the genera Exhippolysmata and Lysmatella. The monophyly of the clade bearing a multi-segmented accessory branch is robust. Within the short accessory branch clade, species with specialized cleaning behaviors form a monophyletic clade, however, the integrity of the clade was sensitive to alignment criteria. Other hippolytid and barbouriid genera used in the analysis are basal to these three groups, including one displaying simultaneous hermaphroditism (Parhippolyte). The two barbouriid species occur in a separate clade, but among hippolytid taxa. Conclusions. The data support the historical morphological division of Lysmata into clades based on accessory branch morphology. The position of the "cleaner" shrimps, indicates that specialized cleaning behavior is a derived trait. The topologies of the cladograms support the monophyly of the barbouriids, but do not support their elevation to familial status. Taxa ancestral to the genus Lysmata display simultaneous hermaphroditism, suggesting that this life history trait evolved outside the genus Lysmata. © 2010 Fiedler et al; licensee BioMed Central Ltd.

Rhyne A.L.,Edgerton Research Laboratory | Rhyne A.L.,Roger Williams University
AACL Bioflux | Year: 2010

Access to peer-reviewed literature is often restricted to a limited segment of the target audience. Barriers are in place to prevent open access of information. In the applied research science of aquaculture, these barriers have slowed progress and innovation. Here, I present a case study of how the internet and hobbyists are transforming both access and flow of information from closed circles to open dialogue within the field of marine ornamental fish rearing. This open approach is leading to innovation a rate remarkably faster and at a lower costs than could have been accomplished by traditional methods. Aquaculture societies, aquarium professionals, hobbyists, and scientists pursuing the captive production of species should embrace this movement. Whether production is for profit, conservation, or pure enjoyment, the free flow of information provides exciting new opportunities.

Rotjan R.D.,Tufts University | Rotjan R.D.,Edgerton Research Laboratory | Dimond J.L.,Western Washington University
Journal of Experimental Marine Biology and Ecology | Year: 2010

A detailed understanding of the dual role of parrotfish as both key herbivores and potentially important corallivores is essential to the study of coral health and reef trophodynamics. Some Caribbean parrotfish regularly consume live coral, and discriminate both among coral species and among colonies within a particular species. While they prefer Montastraea spp. corals, which are dominant Caribbean reef builders, causes of selective and persistent grazing of certain colonies remain unknown. We manipulated coral exposure to parrotfish grazing through a long-term cage exclusion experiment in Belize, comparing initially grazed vs. intact (non-grazed) Montastraea spp. colonies. We measured nutrition-related characteristics (C:N ratio, %C, and %N) as well as defensive characteristics (nematocyst density and skeletal hardness) to determine if any of these variables accurately predicted parrotfish grazing. There were substantial reductions in coral nutritional quality (C:N) associated with parrotfish grazing, although these changes appear to be a consequence rather than a cause of parrotfish selectivity. Likewise, nematocyst densities were suppressed in grazed corals, also likely a result of chronic grazing stress. We found no intraspecific differences in skeletal hardness related to grazing. These results provide further demonstration of the physiological consequences of grazing, but the cause of preferential grazing by parrotfishes on certain Montastraea spp. colonies still requires further investigation. © 2010 Elsevier B.V. All rights reserved.

While single factor diet studies appear to be of simple design, the space constraints in aquaculture caused by the need to filter the aqueous media often create constraints on the implementation of the experimental design. A number of papers have been published in which the experimental design and subsequent analysis is incorrect. This paper reviews the principles of experimental design as it related to single factor diet evaluation studies in aquaculture. By adhering to simple design principles to ensure that experimental units are independent, the data generated by future experiments will be of high quality and results more robust.

Hamilton P.K.,Edgerton Research Laboratory | Cooper L.A.,Edgerton Research Laboratory
Marine Mammal Science | Year: 2010

Abstract: Like most mysticetes, North Atlantic right whale cows generally separate from their calves on their feeding grounds within a year. Right whale life history data from 1993 to 2005 were analyzed to determine the duration of cow/calf associations and where the pair separated. A change occurred with the 2001 cows; 71% of those available stayed with their calves into the second year and this behavior remained elevated for several years. Less experienced cows, independent of their age, were more likely to extend their associations. The occurrence of cow/yearling associations was not related to the length of the cow's previous interbirth interval, used as a proxy for cow condition, but the hypothesis that body condition impacts how long cows nurse their young could not be adequately tested. Seventy-seven percent of the observed cow/yearling pairs also returned to the calving ground, a substantial physiological investment given the 1,450 km plus migration and the fact that they fast there, indicating that factors other than nutrition also influenced the cow's behavior. The concurrent increase in juveniles in the shallow waters of the winter calving grounds may afford naive whales greater protection from predators or provide a social benefit that improves their overall fitness. © 2010 by the Society for Marine Mammalogy.

Browning C.L.,Edgerton Research Laboratory | Rolland R.M.,Edgerton Research Laboratory | Kraus S.D.,Edgerton Research Laboratory
Marine Mammal Science | Year: 2010

Reduced reproductive success has contributed to lack of recovery of the endangered western North Atlantic right whale (Eubalaena glacialis). Here we examined the specific life history period from just before birth through the first year to estimate calf and perinatal losses between 1989 and 2003. The lower bound estimate (17 mortalities from 208 calving events) included documented calf mortalities and presumed deaths from serious injury or disappearance from the sighting record. The upper bound estimated potential calf losses from females with delayed first parturition (>10 yr) and shortened (2 yr) or lengthened (≥4 yr) calving intervals, if the female migrated to the calving ground during these intervals. Because cows were sighted in the calving ground predominantly in years when they were available to calve, adult females sighted there in a possible calving year without a calf were assumed to have experienced a perinatal loss. Twenty-eight potential perinatal losses were detected, bringing the upper bound of calf and perinatal mortality to 45 (3.0 calves/yr). The high frequency of lengthened calving intervals in E. glacialis suggests that abortion and neonatal losses are contributing to lower reproductive success compared to Southern Hemisphere right whales (Eubalaena australis). © 2009 by the Society for Marine Mammalogy.

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