Tom Capo

University of Miami | UM · Division of Marine Biology & Fisheries

For many coral species, the obligate association with phylogenetically diverse algal endosymbiont species is dynamic in time and space. Here, we used controlled laboratory inoculations of newly settled, aposymbiotic corals (Orbicella faveolata) with two cultured species of algal symbiont (Symbiodinium microadriaticum and S. minutum) to examine the...

Regulating partner abunclance may allow symmotic organisms to mediate interaction outcomes, facilitating adaptive responses to environmental change. To explore the capacity for-adaptive regulation in an ecologically important endosymbiosis, we studied the population dynamics of symbiotic algae in reef-building corals under different abiotic context...

The growth and survival of reef corals are influenced by their symbiotic algal partners (Symbiodinium spp.), which may be flexible in space and time. Tradeoffs among partnerships exist such that corals with thermotolerant symbionts (e.g., clade D) resist bleaching but grow more slowly, making the long-term ecosystem-level impacts of different host–...

Opisthobranch molluscs exhibit fascinating body plans associated with the evolution of shell loss in multiple lineages. Sea hares in particular are interesting because Aplysia californica is a well-studied model organism that offers a large suite of genetic tools. Bursatella leachii is a related tropical sea hare that lacks a shell as an adult and...

In order to determine and understand the stable isotope fractionation of 18O and 15N manifested during assimilation of NO3− in marine macro-benthic algae, two species (Ulva sp. and Agardhiella sp.) have been grown in a wide range of NO3− concentrations (2–500 μM). Two types of experiments were performed. The first was one in which the concentration...

In order to determine and understand the stable isotope fractionation of 18O and 15N manifested during assimilation of NO3− in marine macro-benthic algae, two species (Ulva sp. and Agardhiella sp.) have been grown in a wide range of NO3- concentrations (2–500 μM). Two types of experiments were performed. The first was one in which the concentration...

How aging affects the communication between neurons is poorly understood. To address this question, we have studied the electrophysiological properties of identified neuron R15 of the marine mollusk Aplysia californica. R15 is a bursting neuron in the abdominal ganglia of the central nervous system and is implicated in reproduction, water balance,...

Despite the advances in our understanding of aging-associated behavioral decline, relatively little is known about how aging affects neural circuits that regulate specific behaviors, particularly the expression of genes in specific neural circuits during aging. We have addressed this by exploring a peptidergic neuron R15, an identified neuron of th...

Since the 2006 listing of the staghorn coral Acropora cervicornis as threatened under the US Endangered Species Act, interest has increased in its culture for laboratory studies, restoration and ex situ conservation efforts. A pervasive problem in coral culture is substrate overgrowth by algae and other spatial competitors. We conducted a laborator...

Female squirrelfish (Fam. Holocentridae) can accumulate and temporarily sequester copious amounts of zinc (Zn) in their livers. There, it is initially compartmentalized before a subsequent, estrogen-triggered redistribution to the ovaries. Here we show that cellular uptake of Zn is also influenced by estrogen signaling, and that estrogen increases...

To evaluate the effect of elevated pCO(2) exposure on the juvenile growth of the sea urchin Lytechinus variegatus, we reared individuals for three months in one of three target pCO(2) levels: ambient seawater (380 µatm) and two scenarios that are projected to occur by the middle (560 µatm) and end (800 µatm) of this century. At the end of 89 days,...

Previous studies have demonstrated that the euryhaline copepod Acartia tonsa is extremely sensitive to dietborne silver (Ag) exposure, with a 20 % inhibition (EC(20)) of survival occurring when copepods are fed algae with 1.6 μg g(-1) dry weight (dw) Ag, corresponding to a waterborne Ag concentration of 0.46 μg l(-1) Ag. In contrast, 43 μg l(-1) Ag...

Aquaculture methods for queen conch Strombus gigas have been established for several decades. However, there is a need to improve husbandry techniques for the grow out of juveniles. The purpose of this study was to determine the growth and survival of juvenile queen conchs fed artificial diets with increasing levels of a red alga Agardhiella sp. Ag...

Aplysia californica is a marine opisthobranch mollusc used as a model organism in neurobiology for cellular analyses of learning and behavior because it possesses a comparatively small number of neurons of large size. The mollusca comprise the second largest animal phylum, yet detailed genetic and genomic information is only recently beginning to a...

D-Aspartate (D-Asp) can substitute for L-glutamate (L-Glu) at excitatory Glu receptors, and occurs as free D-Asp in the mammalian brain. D-Asp electrophysiological responses were studied as a potential correlate of aging in the California sea hare, Aplysia californica. Whole cell voltage- and current clamp measurements were made from primary neuron...

Land-based sources of pollution have been identified as significant stressors linked to the widespread declines of coral cover in coastal reef ecosystems over the last 30 years. Metal contaminants, although noted as a concern, have not been closely monitored in these sensitive ecosystems, nor have their potential impacts on coral-algal symbioses be...

Over the last three decades, the California sea hare, Aplysia californica, has played an increasingly important role as a model organism in the neurosciences. Since 1995, the National Resource for Aplysia has supported a growing research community by providing a consistent supply of laboratory-reared individuals of known age, reproductive status, a...

Nitrogen availability is an important factor controlling algal growth in marine environments, representing a limiting nutrient throughout much of the global ocean. Anthropogenic inputs to the coastal zone may shift the nutrient regime, leading to questions regarding the extent of anthropogenic nutrient impacts in near-shore environments. A large bo...

Challenges associated with species identification, live collection and laboratory maintenance of billfish larvae have hindered research on their physiology and behavior. In the present study, short-duration neuston net tows in the Straits of Florida yielded 19 live istiophorid billfish larvae, which were immediately placed in a shipboard vertical s...

A rapid, reproducible method is described for extracting and comparing levels of the ether-soluble fish androgen 11-ketotestosterone (11-KT) in blood serum, muscle tissue and surface mucus. Because widely different volumes of extract were recovered after centrifugation from the three sources, it was important to express androgen levels as pg 11-KT/...

SummaryA rapid, reproducible method is described for extracting and comparing levels of the ether-soluble fish androgen 11-ketotestosterone (11-KT) in blood serum, muscle tissue and surface mucus. Because widely different volumes of extract were recovered after centrifugation from the three sources, it was important to express androgen levels as pg...

Since the massive population decline of the long-spined sea urchin, Diadema antillarum, in the early 1980s, the dynamics of coral reef ecosystems in the Caribbean have changed tremendously. The absence of D. antillarum, once a keystone herbivore, has led to macroalgal dominance in many of these reef communities. D. antillarum is not only important...

We conducted a hatchery growth study to describe the variability in growth rates, spawning, and mortality of Aplysia californica in regard to rearing temperature. Animals were housed at a standard hatchery density of five animals per cage, at temperatures of 13, 15, 18, and 21 degrees Celsius. Animals reared at 13 or 15 degrees C grew as much as fo...

Two different hatchery growth studies were conducted to describe the variability in growth rates of Aplysia californica J. G. Cooper, 1863 and develop general growth models for hatchery-raised animals. Aplysia were housed at standard hatchery densities of 6–200 animals cage –1, with cage density decreasing as animals grew. A standard fresh algal di...

Evidence suggests that marine herbivores select for prey items with elevated nitrogen content. We tested this hypothesis with experimental growth studies of the herbivorous gastropod Aplysia californica offered diets of the rhodophyte Gracilaria ferox with varying nitrogen content. A. californica had a sevenfold feeding preference by weight for G....

Although the California sea hare (Aplysia californica) is well known from neurobiological studies and is raised in the laboratory for this purpose, the life history of this species in the laboratory is less well studied. Therefore we conducted a study of the reproductive period of hatchery-born and -raised A. californica in which sibling animals we...

Large-scale experiments using a hydrocyclone, a self-cleaning 50 mum screen, and a UV unit were undertaken to evaluate the treatment efficiency of these commercially available units for preventing the transfer of unwanted species via ships' ballast water. The water flow through the treatment system was approximately 5.7 m(3) min(-1). The effect of...

Postmetamorphic growth and metabolism measurements were obtained on two cohorts of laboratory-reared Diadema antillarum. The cohorts grew linearly from less than 1 mm to over 43 mm. Daily growth averaged 0.097 and 0.11 mm d−1, respectively, for the two cohorts, and was found to differ significantly. Urchin metabolism was examined by a series of sim...

Exuma Sound is a semi-enclosed body of water bounded by islands of the Bahamas. During July 2000, sampling for larval billfish was carried out throughout the Sound's surface waters as well as in adjacent open waters of the Atlantic Ocean. A total of 99 larval billfish (Istiophoridae) was collected. Ninety of the larvae were identifiable as blue mar...

California sea hares (Aplysia californica) were reared from the late juvenile period (approximately day 100 posthatch) to senescence in a laboratory study of growth and maturation at different stocking densities. Temperature, light, and food were controlled, and other seawater parameters such as O2 concentration, pH, and salinity, although not cont...

Billfishes (Istiophoridae [sailfish, marlins, and spearfish] and Xiphiidae [swordfish]) spawn in offshore waters, usually far from land, and, except for sailfish (Istiophorus platypterus), are found inshore only when deep water or currents are near shore. Offshore waters are likely to be less affected by human activity than coastal waters, where an...

The State of Florida’s practice of releasing unmarked early juvenile red drum Sciaenops ocellatus L. to create a recreational fishery in Biscayne Bay, FL, USA, was assessed. Cohorts were reared in ponds to an early juvenile size of ≈ 50 mm total length. Fish were then harvested and transported immediately to release locations within 24 h. Substanti...

Gracilaria ferox J. Agardh was grown continuously in large, outdoor tanks under a pulse-fed nutrient regime for four years. Productivity ranged from 21.4 to 59.2 g d. wt m^-2 d^-1 with a mean of 39.7 g d. wt m^-2 d^-1 over the entire study period. Because the cultures were maintained under non-nutrient limiting conditions, productivity was regulate...

We conducted a 2-year study off Miami, Florida, to verify the presence and seasonality of larval billfish, particularly sailfish (Istiophorus platypterus) and swordfish (Xiphias gladius), and, to examine the feasibility of obtaining laboratory observations on feeding, behavior, and growth. The Gulf Stream's western edge was sampled from April to Oc...

Four head dimensions of red drum Sciaenops ocellatus were individually regressed against total length (TL) to facilitate estimation of the size of hatchery-reared fish recaptured by sport anglers. Head length, postorbital head length, snout length, and eye diameter measurements were obtained from 58 individuals ranging from 130 to 639 mm TL. Each o...

A 66 kDa glycoprotein selected from SDS·PAGE gel profiles of soluble extracts ofLutjanusgriseus was purified by Fast Protein Liquid Chro­ matography technology. A polyclonal antiserum produced to the single­ chained glycoprotein wastested with 14 other lutjanid extracts in Western blots and produced 3 different patterns: strong reactions with L. jo...

Nine mature spotted seatrout Cynoscion nebulosus (seven females and two males) were placed in a recirculating-water culture system at the University of Miami Experimental Hatchery in July 1993. Photoperiod and water temperature were maintained at 14 h light: 10 h dark and 27.5°C. Spotted seatrout held in this controlled photo-thermal culture system...

Swimming efficiency and growth of anchor‐tagged red drum (Sciaenops ocellatus) juveniles were compared with untagged controls. The O2 consumption of fish swimming at different speeds was measured in a Blazka‐type respirometer. Daily growth rates of tagged and untagged red drum were compared over 42 d of feeding fixed rations of live mosquitofish (G...

1. Aplysia californica incorporates toxins and pigments from its red seaweed diet into its body and ink, purportedly as a defense against predation. We tested ink's potential defensive function by assessing the survival of green seaweed-fed (red algal toxin deprived) snails in encounters with a natural predator, the sea anemone Anthopleura xanthog...

1.1. Carbohydrate levels in tissues of Aplysia californica were measured. In animals maintained in the laboratory without feeding for 1–2 weeks, the penis contained the highest concentration of glycogen.2.2. Blood glucose ranged between 2.5 and 4.8mg/dl and averaged 3.2 ± 0.2 mg/dl.3.3. Fed animals had significantly greater tissue glycogen levels t...

Metamorphic competence in the opisthobranch gastropod Aplysia californica Cooper coincides with the appearance of four to six irregularly shaped red spots on the right side of the outer periviceral membrane beneath the larval shell along with a red line overlying the mantle margin. If this pigmented pattern is not manifest, the animal will not resp...