Category Archives: science
Researchers using radiocarbon dating have determined that Greenland sharks, slow-moving giants that live in the cold, dark waters of the North Atlantic, are the longest-living vertebrates on Earth, with one recorded as being 400 years old. Which explains the old Greenland shark quip that goes something like: “God must like practical jokes; why would He make […]
The Paris terrorist attacks weighed pretty heavily on the attendees of COP21 and tightened security around the venues, resulting in protest marches being banned and the unusual sight of shoes in place of marchers.
Conservationists, as expected, took to social media to get in on the conversations denied after being shut out of the French capital and the UN Climate Talks Live Feed gives a great rundown of the discussions from various levels from negotiators to participants and media around the event.
Check out the Civil Society Representatives feed for one – doesn’t include some of the expected organisations and it’s a concern to see climate change skeptic Bjorn Lomberg and downright tool in the top three posters today (Monday 30 November).
Living in the cooler climes of south-eastern Australia, I’m often envious of the crew working at the Lizard Island Reef Research Station and other Great Barrier Reef islands.
While there are some pretty amazing (but less colourful) reef and seafloor communities not far from my home on Port Phillip Bay, I still have to make do with reports on tropical research for my daily warm-water, coral reef region fix. This one below focused on the humble cleaner wrasse and its affect on algae growth – loss of these fish can also lead to increased coral bleaching.
Our first feature scientist was Eva McClure, part of Dr. Lexa Grutter‘s lab team. Dr. Grutter, of the University of Queensland, investigates how the cleaner wrasse, Labroides dimidiatus, influence the ecology of coral reef communities. For the past 15 years, she has run a study on Lizard Island, which sees these fish removed from isolated ‘patch reefs’, and then observes the affect their removal has on the reefs.
Eva has been working for Lexa for the past 3 years. She is currently on Lizard Island wrapping up a 2-year component of Dr. Grutter’s larger, long-term study. In this project, terracotta pavers were placed on the reefs in July 2013, to investigate how the absence of cleaner wrasse may indirectly influence the benthic community (organisms living in the benthic zone are those living at the lowest level of a body of water).
Lexa’s team have found that reefs without cleaner wrasse attract less herbivorous fish than reefs that offer cleaning services (those that have cleaner wrasse present). Reefs without cleaners may therefore have more algae compared to reefs with cleaners, as there are less large herbivorous fish grazing on the benthic community. By placing out algae-coral settlement pavers and periodically measuring the abundance and height of the algae, Eva (as part of Dr. Grutter’s team), hope to make a definitive determination as to whether cleaner wrasse population affects algae levels.
To wrap this project up, a final underwater measurement and photograph is taken (photos 1 and 2), before collecting all 200 pavers, checking them for coral recruits (3) and scraping them of turf algae, calcerous algae, coral recruits and other encrusting organisms. The product is then dried, weighed and taken back to the University of Queensland for analysis.
In Eva’s own words: “It’s exciting and quite satisfying finishing up a 2 year long project like this one, especially when it involves working in a beautiful place like Lizard Island!”
I worked some of the longest days of my career at World Parks Congress and dealt with a variety of event teething issues never experienced before. On the upside, I met some amazing people (including the wonderful Sylvia Earle, who I interviewed for our webtv channel) and worked with a great team from the French Marine Protected Areas Agency. Please make sure you check out our videos at http://oceanplus.tv/en/
Dredging and bottom trawling of Port Phillip Bay in Victoria have destroyed most of the natural shellfish reefs in the 230 years since European settlement of Australia.
This new plan reported in the Age newspaper last week will help to restore shellfish reefs in the bay with the aim of increasing habitat for flathead, snapper and other commercially and recreationally valuable fish.
Shellfish reefs will be re-created on the bottom of Port Phillip Bay in a historic project that aims to improve marine habitats in Victoria’s largest bay.
Researchers say that if the reefs can be successfully established as expected, they would provide healthy habitats for shellfish like mussels and oysters. They would also provide habitat, shelter and food options for fish such as snapper, flathead, rockling and many other fish that live in the bay. They would also help improve water quality.
Shells from mussels, scallops and oysters that have been discarded by the seafood industry and restaurants could be sought as part of the project. They would eventually be placed in the bay at one of three locations, in order to form a base for the early stage of the shellfish reefs. Some artificial material could also be used.
But the project requires more than old shells. Millions of baby oysters and mussels, which will be bred at the Victorian Shellfish Hatchery at Queenscliff, will be used to colonise the reefs in the $270,000 pilot project. The baby oysters and mussels will attach themselves to shells at the hatchery, before they are placed in the water on top of the old shells.
The project, to commence this year, is expected to be formally announced on Saturday by Agriculture Minister Peter Walsh, the minister responsible for fisheries. It will be funded jointly, with $120,000 from the state’s Recreational Fishing Initiative, and $150,000 from The Nature Conservancy, an international organisation that undertakes conservation works around the world.
A patchwork of reefs will be restored at three locations, near Geelong, Chelsea and St Kilda, in about eight to 12 metres of water.
My classmate Dom Lawler deserves most of the credit for producing this video on microplastics, made in less than four days using iMovie for a university assignment on aquatic pollution.
Check the film out and watch some other related one on YouTube if it sparks your interest.
Here’s some quick details on the plastic pollution issue:
– 10% of the 280 million tonnes of plastic produced annually worldwide ends up in the ocean, contributing to 60−80% of all marine debris (Kaposi et al. 2014)
– First reports of plastic litter in the ocean were in the 1970s (Andrady 2011)
– Plastics could take centuries to completely mineralise or biodegrade (Moore 2008)
– 10% of all static fishing gear – including plastic nets, fishing line and ropes – is lost worldwide (FAO 1991)
– In the environmental context, microplastics are regarded as pieces of plastic debris less than 5mm in size
– Studies have found that 267 species of marine organisms worldwide are known to have been affected by plastic debris, a number that will increase as smaller organisms are assessed. (Moore 2008)
References (and other useful video sources)
Plastic Oceans, broadcast on Catalyst, ABC TV1, 6 September 2012:
Plankton film clip: Ren Kyst, Norway www.facebook.com/RenKystFilm
FAO (Food and Agriculture Organization), Canada, 1991. In: Smith, A. (Ed.), Report of the Expert Consultation on the Marking of Fishing Gear, Victoria, British Columbia, Canada, 14–19 July, 1991.
Moore, CJ 2008, ‘Synthetic polymers in the marine environment: A rapidly increasing, long-term threat’, Environmental Research, vol. 108, no. 2, pp. 131-9.
Andrady, AL 2011, ‘Microplastics in the marine environment’, Marine Pollution Bulletin, vol. 62, no. 8, pp. 1596-605.
Kaposi, KL, Mos, B, Kelaher, BP & Dworjanyn, SA 2014, ‘Ingestion of microplastic has limited impact on a marine larva’, Environmental Science and Technology, vol. 48, no. 3, pp. 1638-45.
io9 is generally a scifi website, full of short monologues on the current state of scifi cinema, but occasionally they run very good articles on real science. Like the one below on the issues with sea cucumber harvesting:
Sea cucumbers are in trouble. Everyone knows about the problems that elephants and rhinos face due to poaching, that dolphins face due to drive hunts, and that sharks face when overzealous governments try to convince their constituents that they’re helping them avoid shark attacks. Sea cucumbers may not be as charismatic as their megafaunal counterparts, but they actually provide an important service for reef ecosystems.
They help to keep the sand in reef lagoons and seagrass beds fresh by turning them over, and by feeding on the dead organic matter that’s mixed in with the sand, the nutrients they excrete can re-enter the biological web by algae and coral. Without the sea cucumbers, that sort of nutrient recycling could not occur. It’s also thought that sea cucumbers help to protect reefs from damage due to ocean acidification. Feeding on reef sand appears to increase the alkalinity of the surrounding seawater.
The problem, according to a study conducted by Steven Purcell and Beth Polidoro, is that sea cucumbers are considered a luxury snack. As they explain at The Conversation, dried-out versions of the tropical species retail between $10 and $600 per kilogram in Hong Kong and on mainland China.
There’s actually one species that is sold for $3000 per kilo, dried. Sea cucumbers are thought of as “culinary delicacies,” and often adorn the buffets of festival meals and are served at formal dinners.
There are 377 known species of sea cucumber. Percill and Polidoro’s study shows that the more prized a species is as a delicacy, the more likely the IUCN is to categorize it as vulnerable or threatened – at least for the species they investigated. It’s plain to see that the more expensive the critters are, the more likely they are to be plotted with orange or red dots.
It’s not just a correlation. In most cases, it’s the rarity of a species that drives up the value, leading to exploitation and eventually, extinction. It’s basic supply/demand economics. But the researchers say that for the sea cucumbers they looked at, the causal relationship is reversed. “High-value drives rarity in sea cucumbers, not vice versa,” they write. “None of the naturally rare species are particularly high value.”
Is there anything that can be done to protect these awkward, squishy creatures? “Species-specific bans have been placed on threatened sea cucumbers in a few instances,” the researchers note, “but these regulations do not prevent serial depletion of other species further down the value chain.” Instead, they recommend that a short list of allowable species be created, sort of like Monterey Bay Aquarium’s sustainable seafood card, but for cucumbers. It would exclude threatened species and those most critical for providing ecosystem services to reefs. If sea cucumber fishing can be controlled, the rarer species just might have a fighting chance to survive.
The complex and little-understood nature of deep sea biological communities needs to be further researched before any deep sea mining licenses are granted in the Central and West Pacific.
Speakers at the 4th Regional Training Workshop: Environmental Perspectives of Deep Sea Mineral Activities in Nadi, Fiji, discussed the potential commercial value of deep sea minerals and the expensive but vital research that should be continued to determine the impacts of mining on abyssal plain, seamount and hydrothermal vent communities.
The four-day workshop, organised by the Secretariat of the Pacific Regional Environment Programme (SPREP) and the Secretariat of the Pacific Community (SPC), aims to build on the work undertaken by the SPC-EU Deep Sea Minerals Project to strengthen governance systems in Pacific Island countries and territories to manage and minimise environmental impacts from mining activities.
Mining companies have yet to start any mining operation in the deep sea but are exploring several zones in the Central and West Pacific, searching for rich deposits of manganese nodules, cobalt-rich crusts and seafloor massive sulphides.
Duke University Marine Laboratory director Professor Cindy Van Dover, who has piloted the Alvin submersible to assess deep sea environments, said mining operations could have potentially long-term impacts on the fish, molluscs, sponge and worm communities of the deep sea.
“A single mining event could have the same impact as a volcanic eruption and it would be no big deal. Multiple events would be different,” she said.
“Hydrothermal vents are likely to be more resilient than anything else … but there’s still potential for things to go wrong.”
Prof Dover said hydrothermal vents, a key target for seafloor massive sulphide mining, were also being utilised for their genetic resources to develop medical, pharmaceutical, cosmetic and therapeutic products.
Dr Malcolm Clark, Principal Scientist at New Zealand’s National Institute of Water and Atmospheric Research (NIWA), said the faunal communities in manganese nodule and cobalt-rich crust environments were very different and mining operations should build in large buffer zones to reduce impacts.
Professor Mike Petterson, director of SPC’s Applied Geoscience and Technology Division (SOPAC), also launched the SPC-UNEP/GRID-Arendal Pacific Marine Minerals Assessment Report and presented Mr Samuela Namosimalua, Permanent Secretary, Fijian Ministry of Local Government and Environment, with copies of the report.
More information on the SPC-EU Deep Sea Minerals Project is available at
I was asked by a few people at the Marine Spatial Planning workshop in Suva over the past week to post a few updates on my blog (the original articles I wrote appear on the Secretariat of the Pacific Regional Environment Program website)
What is Marine Spatial Planning, you might ask? Many attendees did this week and among many complex definitions I heard this was the easiest to comprehend: “It is the process of analysing and making recommendations on the distribution of human activities affecting coastal and marine areas. A key goal is to balance ecological, economic, social and cultural objectives.”
26 November 2013, Steve Pogonowski, Marine Spatial Planning, Suva Fiji – Marine spatial planning will become ever more vital as the Pacific islands and territories deal with the impacts of rising sea levels, ocean acidification and ocean warming, attendees at a workshop at the University of the South Pacific in Suva, Fiji, heard yesterday.
The second day of the Marine Spatial Planning workshop looked at climate change and other challenges to central and west Pacific countries and territories, case studies of marine spatial planning across the region and new projects being brought in to assist cross-boundary planning.
Attendees on the second day represented organisations in countries and territories including Wallis and Futuna, Solomon Islands, Tuvalu, French Polynesia, Micronesia and Samoa.
Sangeeta Mangubhai, Senior Programme Officer for IUCN Oceania Regional Office, said she hoped participants would all gain a greater understanding of initiating and carrying out good marine spatial planning.
“One of the things I really liked was listening to the case studies and also hearing some of the regional efforts being made to support countries if they decide to implement marine spatial planning from coastal waters out to their EEZ (Exclusive Economic Zone),” she said.
“Especially for our Pacific Island participants – and there are some here representing their governments – I hope they can gain a real understanding of marine spatial planning is and the role it can play in managing the valuable resources in their countries to achieve the ecological, social and economic outcomes that they want.
“If they undergo a marine spatial planning process, they now realise there are experts and experiences in this region that they can tap into to get support and assistance.”
Discussion topics included the success of Locally Managed Marine Areas in involving communities in conservation; how data collection on tuna fishing can track the effects of climate change; and the importance of local socioeconomic, governance and ecological issues in cross-boundary planning.
François Gauthiez from the French Marine Protected Areas Agency (AAMP) said the workshop had also generated interesting discussions on various software tools and how they can be used to present data simply to help island communities develop their fishing and conservation plans for the future.
After decades of falling stocks of northern (NBT) and southern bluefin tuna (SBT) in fisheries globally, some possible good news: stocks in certain areas appear to be on the rise, according to this Oceana report on a recent ICCAT Standing Committee on Research and Statistics meeting.
I feel like I should automatically qualify that by skipping to the third paragraph of Oceana’s post, which stated:
Scientists say that the models (SCRS is) using are flawed and therefore have little confidence in them, so they will spend 2014 working with more recent data and improving their calculations.
Which makes me think of this piece of gold from 30 Rock:
Just like They Might Be Giants’ Dr Worm, Dr Leo Spaceman is not a ‘real’ doctor but he comes up with some very apt quotes that show how people can trust an academic or medical professional just because they “know science”.
Anyway, some fisheries managers and tuna fishers will be pretty excited about the possible stock rebound but hopefully they’ll err on the side of caution before making any changes to quotas. Here’s some research I put together for a uni report that might shed some light on the Antipodean situation:
“Australia’s SBT catch peaked at 21,500 tonnes in 1982 (Farley, J. H. et al. 2007) and quotas established in 1989 restricted the catch to 5265 tonnes annually.
Japanese long-lining catch peaked at 78,000 tonnes in 1961 and quotas were also introduced to restrict Japan to 6065 tonnes annually.
Illegal, unreported and unregulated fishing for the species is also a major concern with the Commission for the Conservation of Southern Bluefin Tuna finding that ‘substantial and continuous unreported catches of SBT had been taken by longline vessels since at least the early 1990s’ (Polacheck 2012).”
That’s just the Australian and Japanese reported data for SBT – areas of the New Zealand and South African coast are also key fishing grounds, as well as the international waters where self-reporting of catches is still a woefully inadequate system.
In my opinion, we need tougher quotas, not leniency for these ocean hunters.
1. Farley, JH, Davis, TLO, Gunn, JS, Clear, NP & Preece, AL 2007, ‘Demographic patterns of southern bluefin tuna, Thunnus maccoyii, as inferred from direct age data’, Fisheries Research, vol. 83, no. 2-3, pp. 151-61.
2. Polacheck, T 2012, ‘Assessment of IUU fishing for Southern Bluefin Tuna’, Marine Policy, vol. 36, no. 5, pp. 1150-65.