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To examine the potential for the autogenic ecosystem engineers, crustose coralline algae (CCA), to serve as seed banks or refugia for life stages of other species, it is critical to develop sampling protocols that reflect the diversity of life present. In this pilot study on two shallow water species of CCA collected from Raoul Island (Kermadec Islands; Rangitāhua) New Zealand, we investigated two preservation methods (ethanol vs. silica gel), sampled inner and outer regions of the crusts, and used DNA metabarcoding and seven genes/gene regions (16S rRNA, 18S rRNA, 23S rRNA, cox1, rbcL, and tufA genes and the ITS rRNA region) to develop a protocol for taxa identification. The results revealed immense diversity, with typically more taxa identified within the inner layers than the outer layers. As highlighted in other metabarcoding studies and in earlier work on rhodoliths (nodose coralline algae), reference databases are incomplete, and to some extent, the use of multiple markers mitigates this issue. Specifically, the 23S rRNA and rbcL genes are currently more suitable for identifying algae, while the cox1 gene fares better at capturing the diversity present inclusive of algae. Further investigation of these autogenic ecosystem engineers that likely act as marine seed banks is needed. [ABSTRACT FROM AUTHOR]

During late December 2018 a sea star wasting event occurred at Pilot Bay, Tauranga Harbour, North Island/Te Ika-a-Māui, Aotearoa New Zealand. Forty-seven specimens of the asteroid Coscinasterias muricata Verrill, 1867, with a maximum diameter of 50 - 150 mm, were found in varying states of wasting on and between rocks at low tide over an area of ∼70 m at the NW end of Pilot Bay. The wasting event followed a brief period of heavy rain (97.8 mm during the previous 24 h) and was short-lived, with no affected sea stars observed after three days. The affected C. muricata may have had low resilience to changes in water quality, particularly salinity. However, the cause of this wasting event remains unresolved. These opportunistic data suggest that small scale sea star wasting events of this nature may be easily overlooked due to their ephemeral nature.urn:lsid:zoobank.org:pub:C60C26A8-10D7-436D-B2F2-C547DD84BAD8 [ABSTRACT FROM AUTHOR]

Temperature and salinity are important environmental factors affecting the normal functioning of marine animals, particularly animals such as sea urchins living in shallow waters and tide pools. Here, we evaluated the effect of different combinations of temperature and salinity on early embryos of the endemic New Zealand sea urchin Evechinus chloroticus. Animals were collected at Matheson's Bay (36°18'17'S; 174°47'51'E) in north-eastern New Zealand in February 2013. Embryos were exposed to five salinities (29, 31, 34, 35 and 37 ppt) and two temperatures (18 and 21°C) during the first 24 h of development. Low salinity (29 ppt) affected all parameters (fertilization, development rate, gastrulation and normal development), with ca. 50 % of embryos surviving at 29 ppt, whereas seawater temperature only affected development rate and gastrulation. An increase in temperature from 18 to 21°C minimized the negative effect of low salinity (≤31 ppt) on development rate and gastrulation of E. chloroticus. Overall, the results of this study suggest that early embryos of E. chloroticus have developmental plasticity to withstand reductions in salinity up to 29 ppt; however, it is still unknown whether the surviving embryos will be able to complete larval development at low salinities, particularly whether the embryos and larvae are carried into extreme environments such as estuaries where salinity is even lower. Multistressor studies are very important for climate change research as multiple environmental factors will act together in the wild, having major consequences for development and recruitment of marine invertebrates., Introduction Environmental conditions play an important role in the normal functioning of all animals (Willmer 1999), with temperature and salinity of greatest importance for marine animals living in intertidal and [...]