This paper examines the distribution and abundance of mobile epifauna > 1 mm inhabiting 10 species of subtidal brown seaweeds (Phaeophyceae) in northeastern New Zealand. Cammarid amphipods and isopods were the most abundant animals captured, while a diverse group of gastropods was also present at lower densities F~nely structured seaweeds such as Carpophyllum plumosum var. capillifolium and Cystophora retroflexa tended to support far more animals (up to 2000 ind. per 100 g algal wet wt) than did coarsely structured seaweeds. Comparison of epifaunas among C. plurnosum growth forms of varying thallus width indicated that this pattern was due to the morphology of the plants rather than differences in their internal composition. There was a trend for isopods with tubular body shapes to live on algal species with narrow fronds, and for dorso-ventrally flattened isopods to live on algae with wide fronds. Most of the seaweed species held epifaunal assemblages that were distinct from one another in multivariate space, but the individual epifaunal taxa were generally not strongly host-plant specific, w ~ t h most occurring on more than 1 algal species. I t is suggested that most of the epifauna have a weak relationship with their host plant. Epifaunal dens~ties on Ecklonia r a d ~ a t a peaked at 6 m depth, and declined with increasing depth.

/pdf/mobile-epifauna-on-subtidal-brown-seaweeds-in-northeastern-1k56ayjt10.pdf

Mobile epifauna on subtidal brown seaweeds in northeastern New Zealand

Boring crustaceans damage polystyrene floats under docks polluting marine waters with microplastic

I11 . The influence of temperature on salt tolerance . . . . I . Introduction . . . . . . . . . . 2 . Classification of beneficial effects of temperature on salt tolerance 3 . Discussion . . . . . . . . . . . (a) Classification . . . . . . . . . (I) General remarks . . . . . . . . (2) Evaluation of the temperature effects . . . . (b) Other ecological implications . . . . . . (I) Colonization of dilute media in the tropics . . . . (2) Migration . . . . . . . . . IV . General conclusion . . . . . . . . . .

Salt tolerance in crustacea and the influence of temperature upon it

One – Adaptations to intertidal life

Comparative ecophysiology of gammarids (crustacea: amphipoda) from marine, brackish and fresh-water habitats exposed to the influence of salinity-temperature combinations. III. Oxygen uptake

Ten sympatric rocky shore species and 3 brackish-water species of Sphaeromatidae were studied. Rocky shores were classified in terms of substrate and exposure to wave action. Although most of the rocky-shore species occur on all shore classes, vertical and horizontal distribution in each species, as well as densities, vary with substrate and wave action. A close relationship between distribution and breeding exists in the rocky-shore species; maximum differences in the vertical distribution of juveniles and adults occur, together with the highest reproductive capacities, in the species exposed to the greatest wave action. Tolerances to temperature, salinity and desiccation are wider in the species of brackish water and less exposed rocky shores, correlating with the greater variations in these conditions where wave action is reduced. Exoskeletons and pereopods are stouter in the species of more exposed shores, except where the microhabitat affords protection from wave action. In Isocladus armatus, geographic and seasonal variations in relative frequencies of colour forms correlate with differences in environmental temperatures. Under laboratory conditions, the colour forms show differences in tolerances to temperature and salinity.

K. P. Jansen

Papers

Ecological studies on intertidal New Zealand Sphaeromatidae (Isopoda: Flabellifera)