49 research outputs found
A Century of Copepods: The U.S. Fisheries Steamer Albatross
The marine invertebrates of North America received little attention before the arrival of Louis Agassiz in 1846. Agassiz and his students, particularly Addison E. Verrill and Richard Rathbun, and Agassiz's colleague Spencer F. Baird, provided the concept and stimulus for expanded investigations. Baird's U.S. Commission of Fish and Fisheries (1871) provided a principal means, especially through the U.S. Fisheries Steamer Albatross (1882). Rathbun participated in the first and third Albatrossscientific cruises in 1883-84 and published the fist accounts of Albatross parasitic copepods.
The first report of Albatross planktonic copepods was published in 1895 by Wilhelm Giesbrecht of the Naples Zoological Station. Other collections were sent to the Norwegian Georg Ossian Sars. The American Charles Branch Wilson eventually added planktonic copepods to his extensive published works on the parasitic copepods from the Albatross. The Albatross copepods from San Francisco Bay were reported upon by Calvin Olin Esterly in 1924.
Henry Bryant Bigelow accompanied the last scientific cruise of the Albatross in 1920. Bigelow incorporated the 1920 copepods into his definitive study of the plankton of the Gulf of Maine. The late Otohiko Tanaka, in 1969, published two reviews of Albatross copepods. Albatross copepods will long be worked and reworked. This great ship and her shipmates were mutually inspiring, and they inspire us still
Variability of atmospheric dimethylsulphide over the southern Indian Ocean due to changes in ultraviolet radiation
Dimethylsulphide (DMS) is a climatically important component of global biogeochemical cycles, through its role in the sulphur cycle. Changes in ultraviolet radiation (UV) exhibit both positive and negative forcings on the dynamics of production and turnover of DMS and its precursor dimethylsulphoniopropionate (DMSP). In this study we investigate the net forcing of UV on atmospheric DMS. The work is based on a 10-year record of observed DMS at Amsterdam Island in the southern Indian Ocean, and satellite-based retrievals of surface UV and photosynthetically active radiation (PAR). The results show an inverse relationship between UV radiation and atmospheric DMS associated with extreme changes (defined as the greatest 5%) in daily UV, independent of changes in wind speed, sea surface temperature, and PAR
Combined Effects of UVR and Temperature on the Survival of Crab Larvae (Zoea I) from Patagonia: The Role of UV-Absorbing Compounds
The aim of our study was to assess the combined impact of UVR (280–400 nm) and temperature on the first larval stage (Zoea I) of three crab species from the Patagonian coast: Cyrtograpsus altimanus, C. angulatus, and Leucippa pentagona. We determined the survival response of newly hatched Zoea I after being exposed for 8–10 h under a solar simulator (Hönle SOL 1200) at 15 and 20 °C. There was no mortality due to Photosynthetic Active Radiation (PAR, 400–700 nm) or ultraviolet-A radiation (UV-A, 315–400 nm), and all the observed mortality was due to ultraviolet-B radiation (UV-B, 280–315 nm). The data of larval mortality relative to exposure time was best fit using a sigmoid curve. Based on this curve, a threshold (Th) and the lethal dose for 50% mortality (LD50) were determined for each species. Based on the Th and LD50, C. altimanus was found to be the most resistant species, while L. pentagona was found to be the most sensitive to UV-B. For both species of Cyrtograpsus, mortality was significantly lower at 20 °C than at 15 °C; however, no significant differences between the two temperature treatments were found in L. pentagona. Bioaccumulation of UV-absorbing compounds in the gonads and larvae of C. altimanus, and to a lesser extent in C. angulatus, might have contributed for counteracting the impact of UV-B. However, most of the resilience to UV-B observed with the increase in temperature might be due to an increase in metabolic activity caused by a repair mechanism mediated by enzymes
Eurytemora richingsi New species Of Deep Water Calanoid Copepod From The Arctic Ocean
Volume: 89Start Page: 127End Page: 13
Population Dynamics and Distribution of \u3cem\u3eNeomysis Mercedis\u3c/em\u3e and \u3cem\u3eAlienacanthomysis Macropsis\u3c/em\u3e (Crustacea: Mysidacea) in Relation to the Parasitic Copepod \u3cem\u3eHansenulus Trebax\u3c/em\u3e in the Columbia River Estuary
Two species of Columbia River estuary mysids, Neomysis mercedis Holmes and Alienacanthomysis macropsis (Tattersall), were found with a parasitic nicothoid copepod infesting the marsupium of the female mysids. The relationships between the life histories and the spatial and seasonal distributions of the mysids and the ectoparasitic copepod are examined. The remarkably high incidence of parasitism remained stable throughout the year in spite of seasonal fluctuations in the two mysid populations. Neomysis mercedis is an important component in the diet of fishes in other estuaries along the Pacific coast; however, it does not appear to be as important a food resource in the Columbia River estuary. This may be due to the parasite which probably has a significant effect on the population of the mysid hosts
2 Species Of Urocopia, Planktonic Poecilostomatoid Copepods Of The Family Urocopiidae Humes And Stock, 1972
Volume: 99Start Page: 140End Page: 14