Abundant box jellyfish, Chironex sp (Cnidaria: Cubozoa: Chirodropidae), discovered at depths of over 50 m on western Australian coastal reefs

Box jellyfish cause human fatalities and have a life cycle and habit associated with shallow waters (<5 m) in mangrove creeks, coastal beaches, embayments. In north-western Australia, tow video and epibenthic sled surveys discovered large numbers (64 in a 1500 m tow or 0.05 m(-2)) of Chironex sp. very near to the benthos (<50 cm) at depths of 39-56 m. This is the first record of a population of box jellyfish closely associated with the benthos at such depths. Chironex were not widespread, occurring only in 2 of 33 tow videos and 3 of 41 epibenthic sleds spread over 2000 km(2). All Chironex filmed or captured were on low to medium relief reefs with rich filter feeder communities. None were on soft sediment habitat despite these habitats comprising 49% of all sites. The importance of the reef habitat to Chironex remains unclear. Being associated with filter feeder communities might represent a hazard, and other studies have shown C. fleckeri avoid habitats which represent a risk of entanglement of their tentacles. Most of our observations were made during the period of lowest tidal current flow in the morning. This may represent a period favourable for active hunting for prey close to the seabed

Abiotic factors influencing biomass accumulation of green tide causing Ulva spp. on Pyropia culture rafts in the Yellow Sea, China

Annually recurrent green-tides in the Yellow Sea have been shown to result from direct disposal into the sea of fouling Ulva from Pyropia aquaculture. The role abiotic factors play in Ulva biomass accumulation on rafts was studied to find ways to mitigate this problem. Dissolved inorganic nitrogen (DIN) was very high at all sites, but the highest Ulva biomass was associated with the lowest DIN and anthropogenic N. Under luxuriant background nutrient conditions, variability in temperature and periods of emersion, rather than pH, light and salinity determined Ulva biomass. Two dominant species of Ulva displayed differing tolerances to temperature and desiccation which helped explain why Ulva prolifera dominates floating green-tides. Rather than trying to mitigate green tides only by reducing nutrient pollution, an earlier harvest of Pyropia in southern Jiangsu Province especially before temperatures increase greatly above 10 degrees C during April, could reduce the biomass of U. prolifera disposed from rafts. Crown Copyright (C) 2016 Published by Elsevier Ltd. All rights reserved

Invasive Species in Forests and Rangelands of the United States

This open access book describes the serious threat of invasive species to native ecosystems. Invasive species have caused and will continue to cause enormous ecological and economic damage with ever increasing world trade. This multi-disciplinary book, written by over 100 national experts, presents the latest research on a wide range of natural science and social science fields that explore the ecology, impacts, and practical tools for management of invasive species. It covers species of all taxonomic groups from insects and pathogens, to plants, vertebrates, and aquatic organisms that impact a diversity of habitats in forests, rangelands and grasslands of the United States. It is well-illustrated, provides summaries of the most important invasive species and issues impacting all regions of the country, and includes a comprehensive primary reference list for each topic. This scientific synthesis provides the cultural, economic, scientific and social context for addressing environmental challenges posed by invasive species and will be a valuable resource for scholars, policy makers, natural resource managers and practitioners

A Review of Sea Cucumber Aquaculture, Ranching, and Stock Enhancement in China

Sea cucumber aquaculture has flourished as a result of increasing demand coupled with declining wild fisheries and has been facilitated by technical progress in the production and grow-out phase of larvae and small juvenile sea cucumbers. China has developed a large and successful sea cucumber aquaculture industry based on the temperate species Apostichopus japonicus (Selenka, 1867). China consumes most of its domestic sea cucumber production (193, 705 tons: 2013), exporting only a few dozen tons. Much of the success of sea cucumber aquaculture in China came from advances in culture methods, especially for the early stages of broodstock conditioning, larval production and settlement, and the critical early juvenile development stage. These artificial approaches to production are a precondition for all aquaculture models, and the scientific procedures and management protocols must be strictly adhered to for success. Similarly, the grow-out phase of sea cucumber production in China has evolved from attempts using disused fish and shrimp ponds to new, dedicated ponds developed to meet the more sensitive requirements of sea cucumbers for water quality and substrate type and to the use of ocean ranching. Various diseases have affected this industry and become barriers to its sustainable development. To achieve higher survival rates and better production quality, the trend has been toward ocean ranching of sea cucumbers and stock enhancement, and production levels have increased significantly in recent years. While cost-effective methods for sea cucumber aquaculture close to their point of consumption is good news for wild stocks of sea cucumbers in different parts of the world, there is a potential downside in the environmental impact of such extensive production methods. The influence of sea cucumber aquaculture on the environment and the influence of the environment on sea cucumber aquaculture are important issues relating to ecological security and sustainability

Role of winds and tides in timing of beach strandings, occurrence, and significance of swarms of the jellyfish Crambione mastigophora Mass 1903 (Scyphozoa: Rhizostomeae: Catostylidae) in north-western Australia

Very large swarms of the red jellyfish Crambione mastigophora in north-western Australia disrupt swimming on tourist beaches causing economic impacts. In October 2012, jellyfish stranding on Cable Beach (density 2.20 +/- A 0.43 ind. m(-2)) was estimated at 52.8 million individuals or 14,172 t wet weight along 15 km of beach. Reports of strandings after this period and up to 250 km south of this location indicate even larger swarm biomass. Strandings of jellyfish were significantly associated with a 2-day lag in conditions of small tidal ranges (< 5 m). More than 90% of strandings occurred 2 days after winds were blowing onshore, but with the small number of days when satellite wind data were available during the study period, this result was not statistically significant. Dedicated instrument measurements of meteorological parameters, rather than the indirect measures used in this study (satellite winds and modelled currents) may improve the predictability of such events and help authorities to plan for and manage swimming activity on beaches. We also show a high incidence of predation by C. mastigophora on bivalve larvae which may have a significant impact on the reproductive output of pearl oyster broodstock in the region