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Each sampling event fished at a constant depth, estimated bywire angle and length ofwire deployed.Af ter washing, pellets were dissolved in NCS II solubilizer. Its primaryhabitats are shallow saltmarsh creeks, in which it may encounter seasonal temperature ranges of C inwinter to C in summer.Fundulus eggs typically develop out of the water for periods up to weeks during the spring and summer, which makes them particularly vulnerable to UVB.Immediately following irradiation, specimens used in the PER studies were exposed to continuous photoreactivating light and then sacrificed at inter vals for evaluation of CPD burden.PER rates were calculated by fitting the time course of CPD disappearance to the function CPD eR, where CPD is the percentage change in dimer concentration, R is the relative PER rate, andtis the postUV irradiation time. R was calculated by determin ing the leastsquares slope of the logarithmtransformed relationship between CPD and time.Dark repair was evaluatedwith an identical protocol, but specimens were held in the dark for the duration of postirradiation sampling.lar vaeanterior. The sample sizes for chaetognaths and polychaetes were small, but half or more of these specimens also contained DNA damage, albeit at lower levels than those of the ichthyofauna.Thus, PER appears to be the major DNA repair system available to these marine species, but the ontogeny of PER and NER remains to be examined.DNA damage is plotted vs.Hunters weighted UVB for each day during which samples were collected.These differences are exemplified by the time required for repair of in itial CPD loads, which ranged from to hfor the icefish and krill. Postirradiation time, in h, is represented by t.PER rates for the eurythermalkillifish were determined at three acclimation temperatures; the solid line is the bestfitting linear regression and its dotted extensions extrapolate the trend in the data to lower and higher temperatures.DNA damage was greater in the fish specimens than in the other taxa examined.At present, the data required to discriminate between these possibilities is only suggestive.However, the expression and function of DNA repair systems during icefish development remains to be determined.Assessment of the potential ef fect of elevated solar UVB on marine organ isms requires consideration of light attenuation, mix ing depth and sea state.Because we cannot reconstruct the precapture depth historyof indiv idual zooplankters in our field collections, it is not surprising that we found no relationship between collection depth and CPD load.Furthermore, diel and ontogenetic patterns of depth distribution are required to fully evaluate the impact of solar UVB on any marine taxon.We suggest, therefore, that buoyant, relatively nonmobile fish eggs may ser ve as ef fective passive in situ dosimeters, but accurate assessment of the ef fect of solar UVB on highly mobile taxawill require knowledge of vertical mix ing rates and diel migratorybehav ior.Our data suggest, however, that the ef fect on organ isms occupying trophic levels other than primaryproducers may be substantial.They generally have translar vae, andor adult stages that are pelagic, parent eggs, plankton ic, and of ten remain in sur face waters for months. Bang Research Fellowship at the Marine Biological Laborator y, Woods Hole, MA. ElSayed, S, ed. in Biologyof Antarctic Fish, eds. di Prisco, G, Maresca, B. Tota, B. Polar Biol. Targett, T. E. Polar Biol. Bidigare, R. R. in Biologyof Antarctic Fish, eds. di Prisco, G, Maresca, B. Tota, B, pp, rebmetpe Snotseugybded aonlwoD

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