Since the advent of recreational and scientific SCUBA diving in the 1950s, coral reefs have become one of the most studied and appreciated marine ecosystems. Direct human observations have been essential to many scientific discoveries. However, most in-water experiences are limited to short durations (tens of minutes to ~1 hour), shallow depths (surface to ~30 m), and calm sea conditions, leaving much of the reef environment u...

Morphometrics and meristics are measurable and countable traits, respectively, that are under simultaneous control by genetic and/or environmental factors. Resolving morphometric and meristic spatial variation can be a useful technique for identifying population structure and connectivity. The present study investigated morphometric and meristic character variation within three flounder species, sand flounder ( Rhombosolea ple...

Aim Fisheries ecosystems are subject to long‐term shifts in food web structure as a result of exploitation and environmental change. These shifts can be gradual and unresolved by decadal‐scale time series. The aim of our study was to determine long‐term legacy effects of overexploitation and changes to the composition of basal organic matter sources on the trophic structure of marine food webs. Location New Zealand. Time perio...

The dynamics of freeze and thaw events in Antarctic sea ice impart chemical changes in the underlying sea water. Trace metals in sea ice and accumulated through deposition of dust are released into sea water as sea ice breaks up in spring. Clams such as Laternula elliptica incorporate a record of these and associated chemical dynamics in their carbonate shells. In 2012, we collected samples of L. elliptica from three sites alo...

Organic matter produced by the sea ice microbial community ( SIMC o) is an important link between sea ice dynamics and secondary production in near‐shore food webs of Antarctica. Sea ice conditions in McMurdo Sound were quantified from time series of MODIS satellite images for Sept. 1 through Feb. 28 of 2007–2015. A predictable sea ice persistence gradient along the length of the Sound and evidence for a distinct change in sea...

Trace element concentrations within fish otoliths act as biological tags and environmental chronometers within aquatic environments. Linking patterns in elemental concentrations within ice fish otoliths to sea ice dynamics allows us to better understand the chemical dynamics of ice‐covered environments. Here laser ablation inductively coupled plasma mass spectrometry was used to measure the concentrations of conservative and b...

In the New Zealand fjords, hydrogen sulfide production from decomposing forest litter is used by chemoautotrophs to fix CO 2[aq] and support benthic food webs. We used quantitative surveys and stable isotope analyses to investigate the contribution of chemoautotrophy to shallow (50 m) and deep (400 m) benthic communities in Doubtful and Bradshaw Sounds. Prevalence of bivalve‐chemoautotroph symbioses varied between shallow site...

Field surveys and laboratory experiments were used to investigate the influence of the physical environment on variability in δ 13 C and δ 15 N signatures of Ulva pertusa , an abundant macroalgae inhabiting the low salinity layer (LSL) of Doubtful Sound, a New Zealand fjord. Field surveys revealed significant spatial variability in δ 13 C (‐18% to ‐12%) and δ 15 N (0% to 6%). δ 13 C was enriched at high irradiance sites and de...

New Zealand's 14 deep‐water fiords possess persistent salinity stratification and mean estuarine circulation that may serve to isolate populations of marine organisms that have a dispersal larval phase. In order to investigate this idea, we analysed the population structure of the sea star Coscinasterias muricata using a mitochondrial DNA marker. Genetic differentiation among populations of C. muricata was analysed using 366 b...

The reproductive cycle of Evechinus chloroticus (Val.) was examined at three (outer, mid, and inner) sites in Doubtful Sound, Fiordland over a 3‐year period. We found that sea urchins from all three populations had an annual gametogenic cycle, the timing of which was temporally and spatially consistent. Inter‐individual variation in the gametogenic cycle was noted within each population, however, initiation of gametogenesis wa...

Calorific content was measured in 28 species of New Zealand macroalgae. Values ranged from 1.04 to 3.34 kcal g‐1 dry weight (wt), 3.03–5.18 kcal g‐1 ash‐free dry wt, and 0.13–1.75 kcal g‐1 wet wt. Seasonal variation in calorific content was measured in two of these species, Macrocystis pyrifera and Ulva lactuca , both of which showed clear changes in energy content over a 1‐year period. Factors affecting variation in calorific...

To better understand the spatial distribution of recruitment in the northern California red sea urchin ( Strongylocentrotus franciscanus ) population, we sampled size distributions at each of 12 locations in 1995 and 1996, two of those locations in 1994, and 5 of those locations in 1997. An index of recent recruitment in these size distributions and an estimate of density of recent recruitment reflect a similar spatial pattern...

123°00′W) occurs primarily during relaxation from upwelling, when warm water flows poleward from the Gulf of the Farallones. During 1994 and 1995 we sampled planktonic larval distributions and hydrography both south and north of Point Reyes during upwelling to test whether high concentrations of crab and rockfish larvae were concentrated in the source of the relaxation flow to the south of Point Reyes. An upwelling plume off P...