Seagrass ecosystem contributions to people's quality of life in the Pacific Island Countries and Territories

Seagrass ecosystems provide critical contributions (goods and perceived benefits or detriments) for the livelihoods and wellbeing of Pacific Islander peoples. Through in-depth examination of the contributions provided by seagrass ecosystems across the Pacific Island Countries and Territories (PICTs), we find a greater quantity in the Near Oceania (New Guinea, the Bismarck Archipelago and the Solomon Islands) and western Micronesian (Palau and Northern Marianas) regions; indicating a stronger coupling between human society and seagrass ecosystems. We also find many non-material contributions historically have been overlooked and under-appreciated by decision-makers. Closer cultural connections likely motivate guardianship of seagrass ecosystems by Pacific communities to mitigate local anthropogenic pressures. Regional comparisons also shed light on general and specific aspects of the importance of seagrass ecosystems to Pacific Islanders, which are critical for forming evidence-based policy and management to ensure the long-term resilience of seagrass ecosystems and the contributions they provide

Seagrass ecosystems of the Pacific Island countries and territories: a global bright spot

Seagrass ecosystems exist throughout Pacific Island Countries and Territories (PICTs). Despite this area covering nearly 8% of the global ocean, information on seagrass distribution, biogeography, and status remains largely absent from the scientific literature. We confirm 16 seagrass species occur across 17 of the 22 PICTs with the highest number in Melanesia, followed by Micronesia and Polynesia respectively. The greatest diversity of seagrass occurs in Papua New Guinea (13 species), and attenuates eastward across the Pacific to two species in French Polynesia. We conservatively estimate seagrass extent to be 1446.2 km2, with the greatest extent (84%) in Melanesia. We find seagrass condition in 65% of PICTs increasing or displaying no discernible trend since records began. Marine conservation across the region overwhelmingly focuses on coral reefs, with seagrass ecosystems marginalised in conservation legislation and policy. Traditional knowledge is playing a greater role in managing local seagrass resources and these approaches are having greater success than contemporary conservation approaches. In a world where the future of seagrass ecosystems is looking progressively dire, the Pacific Islands appears as a global bright spot, where pressures remain relatively low and seagrass more resilient

A Novel Method of Assessing Bioerosion by the Sea Urchin Echinometra sp. A on a Fijian Reef

Sea urchins are major substratum eroders of coral reefs and the calcium carbonate condition of coral reefs may therefore reflect the abundance of sea urchins. The omnivorous urchins, Echinometra spp. are known as ?rock -borers? and are agents of large-scale bioerosion, particularly in the Caribbean, Eastern Pacific and Western Indian Ocean. By burrowing into coral rocks they protect themselves from predators, wave and current action, and to some extent from desiccation at low tide. Bioerosion estimates are known for a few specific reefs only. Although the Echinometra sp. A have not been named yet, they were mistaken for Echinometra mathaei for long in Fiji. This novel study attempted to estimate bioerosion rates of the low but consistent numbers of sea urchins, Echinometra sp. A (green-white-tipped) on the Nukubuco reef, Fiji by calculation of the net carbonate accumulation. Cage experiments reported bioerosion rates (kg CaCO3/m2/urchin/d) of 35-37 x 10-3 at the reef crest and 30-43 x 10-3 at the reef flat. This method of assessing bioerosion showed both strengths and weaknesses. However, the Nukubuco reef balance between reef growth and reef destruction is shifting, with bioerosion becoming the dominant process

A novel method for assessing bioerosion by the sea urchin Echinometra sp. on a Fijian reef

Sea urchins are major substratum eroders of coral reefs and the calcium carbonate condition of coral reefs may therefore reflect the abundance of sea urchins. The omnivorous urchins, Echinometra spp. are known as “rock -borers” and are agents of large-scale bioerosion, particularly in the Caribbean, Eastern Pacific and Western Indian Ocean. By burrowing into coral rocks they protect themselves from predators, wave and current action, and to some extent from desiccation at low tide. Bioerosion estimates are known for a few specific reefs only. Although the Echinometra sp. A have not been named yet, they were mistaken for Echinometra mathaei for long in Fiji. This novel study attempted to estimate bioerosion rates of the low but consistent numbers of sea urchins, Echinometra sp. A (green-white-tipped) on the Nukubuco reef, Fiji by calculation of the net carbonate accumulation. Cage experiments reported bioerosion rates (kg CaCO3/m2/urchin/d) of 35-37 x 10-3 at the reef crest and 30-43 x 10-3 at the reef flat. This method of assessing bioerosion showed both strengths and weaknesses. However, the Nukubuco reef balance between reef growth and reef destruction is shifting, with bioerosion becoming the dominant process

Seasonal changes in the Sargassum populations on a fringing coral reef, Magnetic Island, Great Barrier Reef region, Australia

Sargassum populations are one of the most conspicuous features of both the reef flats and the reef slopes of fringing coral reefs in the Great Barrier Reef region, in terms of their widespread occurrence and often high standing crop. Although an important element of the benthic community on inshore reefs, Sargassum spp. are generally absent from mid- and outer shelf reefs in the region. In this study, the temporal and spatial distribution patterns of the Sargassum populations on a fringing reef flat in Geoffrey Bay (Magnetic Island) were investigated quantitatively. Data on biomass, cover, density, mean thallus length and reproductive condition were collected at three sites on the reef flat over a 13 month period from March 1986 to March 1987. The Sargassum populations in Geoffrey Bay showed marked seasonal changes in growth and development. They exist as dense stands of large thalli in the warmer months, but persist largely as basal parts only (including the holdfasts with short primary axes) in the cooler months. The observed seasonality is discussed with reference to possible causal factors

Variation in abundance and spatial distribution of ecomorphs of the sea urchins, Echinometra sp. nov A and E. sp nov C on a Fijian reef

This paper presents novel spatial distribution and abundance patterns of ecomorphs of Echinometra sp. nov A andE. sp. nov C (hereafter referred to as E. sp. A and E. sp. C, and collectively as Echinometra spp.).Echinometraspp. were surveyed on the Nukubuco Reef, to determine the within-reef variations in size-frequency and density atseveral spatial scales [between positions (east versus west), zones (crest versus flat), sites and quadrats]. The scalesofvariation were greatest for both species between positions and zones. Echinometrasp. A was more readily foundon the calmer flats while E. sp. C preferred the high-energy crests. The distribution of ecomorphs of Echinometraspp.varied between habitats (position x zone). Echinometrasp. A ecomorphs were more abundant on all locationsand showed different size-class distributions compared with E. sp. C. Greater urchin numbers were observed onboth zones of the eastern position than the western position. Echinometrasp. A showed marginal aggregationpattern while E. sp. C showed a stronger tendency to cluster