30 research outputs found
Marine flora and fauna of the Eastern United States Anthozoa: Acitniaria, Corallimorpharia, Ceriantharia, and Zoanthidea
This key includes 60 species of sea anemones and their relatives in the orders Actiniaria, Corallimorpharia, Ceriantharia, and Zoanthidea. Species from the intertidal zone, continental slope, and deep sea are included over a geographic range from Atlantic Canada to approximately South Carolina. In addition to the illustrated key itself, characteristics of each species are summarized in tabular form, including morphology, distribution, and types and sizes of cnidae. Ecological and taxonomic information on each species are also included in an annotated species list. (PDF file contains 76 pages.
Urban-related distribution patterns of an iconic Salish Sea mesopredator, the giant Pacific octopus (Enteroctopus dofleini)
Like many coastal areas globally, the Salish Sea has undergone rapid urbanization over recent decades. Terrestrial research suggests urbanization facilitates a variety of mesopredators by enhancing food and shelter resources and by limiting apex predation. Yet urbanizationâs effect on mesopredators in the marine environment has rarely been examined. The giant Pacific octopus, Enteroctopus dofleini, is an iconic mesopredator of the Pacific Northwest due to its size and cognition, and is thought to reach a particularly large maximum size in inland waters of the Salish Sea. We examined the spatial distribution patterns and habitat use of giant Pacific octopus in Puget Sound using a combination of field surveys and citizen-contributed data from the Reef Environmental Education Foundation (REEF). Specifically, we sought to determine: (1) Whether octopus distribution was related to land-based urbanization indices, (2) Whether octopus abundance correlated with anthropogenic debris, and (3) Whether octopus diets differed relative to urbanization intensity. Our findings suggest that effects from urbanization may depend heavily on the depth of benthic habitats. In deeper subtidal areas (\u3e 24 m), the estimated probability of octopus occurrence increased with adjacent land-based urbanization. Conversely, octopus in shallower subtidal zones (\u3c 18 m) were less likely to occur as urbanization intensity increased. This pattern appears to be unrelated to utilization of prey resources by octopus, as accompanying surveys of octopus middens showed no depth-specific differences in diet relative to urbanization. However, additional video transect surveys at paired sites with high versus low concentrations of anthropogenic debris indicated that artificial structures, which may be extensive in deep-water habitats within heavily urban areas, facilitate higher octopus abundances by serving as den sites. We suggest that den provisioning by urban artificial structures may be a key mechanism driving urban-related distribution patterns of giant Pacific octopus, and should be explored further through future research
Circadian Clock Gene Expression in the Coral Favia fragum over Diel and Lunar Reproductive Cycles
Natural light cycles synchronize behavioral and physiological cycles over varying time periods in both plants and animals. Many scleractinian corals exhibit diel cycles of polyp expansion and contraction entrained by diel sunlight patterns, and monthly cycles of spawning or planulation that correspond to lunar moonlight cycles. The molecular mechanisms for regulating such cycles are poorly understood. In this study, we identified four molecular clock genes (cry1, cry2, clock and cycle) in the scleractinian coral, Favia fragum, and investigated patterns of gene expression hypothesized to be involved in the corals' diel polyp behavior and lunar reproductive cycles. Using quantitative PCR, we measured fluctuations in expression of these clock genes over both diel and monthly spawning timeframes. Additionally, we assayed gene expression and polyp expansion-contraction behavior in experimental corals in normal light:dark (control) or constant dark treatments. Well-defined and reproducible diel patterns in cry1, cry2, and clock expression were observed in both field-collected and the experimental colonies maintained under control light:dark conditions, but no pattern was observed for cycle. Colonies in the control light:dark treatment also displayed diel rhythms of tentacle expansion and contraction. Experimental colonies in the constant dark treatment lost diel patterns in cry1, cry2, and clock expression and displayed a diminished and less synchronous pattern of tentacle expansion and contraction. We observed no pattern in cry1, cry2, clock, or cycle expression correlated with monthly spawning events suggesting these genes are not involved in the entrainment of reproductive cycles to lunar light cycles in F. fragum. Our results suggest a molecular clock mechanism, potentially similar to that in described in fruit flies, exists within F. fragum
Morphological Variability during Longitudinal Fission of the Intertidal Sea Anemone, Anthopleura elegantissima (Brandt)
The sea anemone Anthopfeura elegantissima forms clonal aggregations
on rocky shores along the Pacific Coast of North America by a process of
longitudinal fission. Fission can occur by lateral stretching of the column and
separation of the two halves followed by internal regeneration of parts of the
actinopharynx and of the column. Two new directive mesenteries, one siphonoglyph,
and several pairs of mesenteries flanking the directives also form .
Alternatively, large individuals appear to form new directive mesenteries and
siphonoglyphs well in advance of divisio
THE REGULATION OF ASEXUAL REPRODUCTION AND INDETERMINATE BODY SIZE IN THE SEA ANEMONE ANTHOPLEURA ELEGANTISSIMA (BRANDT)
Volume: 158Start Page: 370End Page: 38
AGONISTIC BEHAVIOR IN THE INTERTIDAL SEA ANEMONE ANTHOPLEURA XANTHOGRAMMICA
Volume: 166Start Page: 457End Page: 47
THE ALLOMETRY OF FEEDING, ENERGETICS, AND BODY SIZE IN THREE SEA ANEMONE SPECIES
Volume: 161Start Page: 152End Page: 17
Community structure, water column nutrients, and water flow in two Pelican Cays ponds, Belize
Volume: 471Start Page: 105End Page: 12
Data from: Individual marking of soft-bodied subtidal invertebrates in situ - a novel staining technique applied to the giant plumose anemone Metridium farcimen (Tilesius, 1809)
The ability to recognize individuals and track growth over time is crucial to population dynamics research as well as studies of animal behavior. Invertebrates are particularly difficult to track as they often molt, have regenerative capabilities, or lack hard parts to attach markers. We tested, in laboratory and field studies, a new way of marking sea anemones (order Actiniaria) by injection of three vital stains (i.e., neutral red, methylene blue, and fluorescein). Neutral red and methylene blue did not affect growth or survival, but fluorescein was lethal at high concentrations. Marked individuals could be identified up to seven months after injection with neutral red, six weeks with methylene blue, and three days with low concentrations of fluorescein. Neutral red could be used for long-term monitoring of growth and survival in the field, and in combination with methylene blue could be used to mark individuals in distinguishable patterns for short-term studies such as examining predator-prey interactions, movement of individuals, and recruitment survival
Sweeper Tentacles in a Gorgonian Octocoral: Morphological Modifications for Interference Competition
Volume: 175Start Page: 378End Page: 38