Stable carbon and nitrogen isotope ratios of benthic invertebrates and their potential food sources, such as suspended particulate organic matter (POM), benthic microalgae, attached algae and seagrass, were identified in Dong-dae Bay during the winter. The carbon stable isotope ratios demonstrate that filter feeders, such as oysters (−19.5 ± 1.0‰), use benthic microalgae (−21.2 ± 0.2‰) as a major food, and polychaetes such as Glycera spp. (−14.0 ± 0.6 ‰) preferentially use meiofauna, such as nematodes (−14.0 ± 0.4‰) and copepods (−13.3 ± 1.0‰). These meiofauna may feed on mixed resources (including bacteria) with the isotope ratios between benthic microalgae (−21.2 ± 0.2‰) and seagrass (−9.3 ± 01.0‰). These findings are consistent with the trophic enrichment in the nitrogen isotope ratios (by 3–4‰) between consumers and food sources. Moreover, the results of the MixSIR model based on the observed isotope ratios suggest a large seagrass contribution to the food sources of benthic organisms such as meiofauna (~53.7–62.6%) and macrobenthos (~41.1–68%) through the food web. This model additionally suggests a relatively large contribution of benthic microalgae to the food sources of filter feeders (i.e. 26.4% for oysters).

The morphology of the first zoea of Gnathophyllum elegans is described from laboratory-reared material for the first time and analysed in detail with light and scanning electron microscopy. For systematic reasons, morphological characteristics in G. elegans are compared with those in Gnathophyllum americanum, Periclimenes amethysteus, a representative of the subfamily Pontoniinae and the closely related Hymenocera picta (Decapoda: Caridea: Hymenoceridae). We observed differences in the morphology of both Gnathophyllum-larvae, such as the number and arrangement of certain setae. Thus, larvae of the two Gnathophyllum species can be readily distinguished from each other. Further differential diagnosis with P. amethysteus confirms a high similarity between Gnathophyllum-larvae and larvae in the subfamily Pontoniinae, as already mentioned in earlier publications. The systematic relationships of the Gnathophyllidae, Hymenoceridae and Pontoniinae are discussed based on zoeal characters.

A floristic study of the marine plants and algae at Luhuitou reef, Sanya Bay, Hainan Island, China, was conducted during the rainy (October 2008 and November 2010) and dry seasons (April 2009 and February 2012). Specimens were collected in the upper subtidal zone (from 0.5 to 3 m depth at low tide). A total of 156 taxa were collected, including 143 macrophyte species (90%), 12 blue–green algal species (10%), and the seagrass, Thalassia hemprichii. The most diverse group was the Rhodophyta (79 taxa or 55%), followed by the Chlorophyta (38 taxa or 25%) and then the Phaeophyceae (26 taxa or 20%). In the upper subtidal zone, macroalgae formed two types of communities: polydominant communities of turf-forming algae and monodominant and bidominant communities of foliose or fleshy algae. Seasonal changes occurred in the dominant species, which appear to be caused by periodic annual events of thalli detachment and subsequent community succession. In spite of heavy pollution from dissolved inorganic nitrogen and phosphorus in Sanya Bay, the subtidal flora has not undergone any dramatic changes in species numbers or composition and is similar to that of unpolluted regions in the Indo-Pacific.

An assemblage of killer whales that has been sighted in waters off the west coast of the British Isles and Ireland has previously been shown to be isolated from other North Atlantic killer whale communities based on association patterns. By applying a Bayesian formulation of the Jolly–Seber mark-recapture model to the photo-identification data compiled from opportunistic photographic encounters with this population of killer whales, we show that such sparse and opportunistically-collected data can still be valuable in estimating population dynamics of small, wide-ranging groups. Good quality photo-identification data was collected from 32 encounters over 19 years. Despite a cumulative total of 77 identifications from these encounters, just ten individuals were identified and the remaining 67 identifications were re-sights of these ten animals. There was no detected recruitment through births during the study and, as a result, the population appears to be in a slight decline. The demography of the population was highly skewed towards older individuals and had an unusually high ratio of adult males, and we suggest that demographic stochasticity due to a small population size may be further impacting the population growth rate. We recommend that this population be managed as a separate conservation unit from neighbouring killer whale populations.

The study presents Cladorhizidae collected during Ifremer cruises in the Atlantic Ocean from 1981 to 2004. Fifteen species are described from the genera Abyssocladia, Asbestopluma, Chondrocladia and Cladorhiza, with complete descriptions of five new species. While a couple of species were collected at 670–1010 m depth at the Rockall Bank, most species were collected at middle to lower bathyal and abyssal depths (~2000–5000 m), ranging from the northern Atlantic to the Mid-Atlantic Ridge and the coast of Africa at Gabon–Congo. A biogeographic analysis of currently known Arctic, Atlantic and some Antarctic species shows that the majority of included cladorhizids are described from the north-east Atlantic and Arctic Oceans while a lower number of species are known from other parts of the Atlantic Ocean. Large regions are poorly investigated, and previously undescribed species can be expected when sampling in these areas. A regional mostly endemic cladorhizid fauna is predicted for shelf and upper slope areas. Species in the lower bathyal and abyssal seem on the other hand to have a wider geographical distribution.

Reproductive aspects of the intensively traded ornamental shrimp Lysmata boggessi were examined. Abundance, reproductive biology (fecundity, reproductive output and egg size) and population structure (frequency distribution, size at sex phase change and sex phase ratio) were examined at three different fishing grounds off south and west-central Florida between May 2011 and February 2012. Fishery-dependent densities of L. boggessi varied between 2.51 ± 1.39 and 13.05 ± 9.30 shrimps per 1000 m2 at two different localities. The proportion of brooding shrimp varied considerably at one locality during two different dates, suggesting reproductive seasonality. Reproductive output increased linearly with shrimp body weight (SBW) at one locality (May 2011), but scaled negatively with SBW at a second locality (January–February 2012). Lastly, no correlation between embryo size and shrimp carapace length (CL) was recorded at one locality (May 2011), but a slight negative correlation between embryo size and CL was found at the second locality (January–February 2012). Lysmata boggessi might be experiencing trade-offs between different reproductive parameters driven by environmental, probably seasonal, conditions during the year. All of this information needs to be considered in assessing shrimp stocks and establishing a sustainable management plan.