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Sam Andrews
"I don’t think that I can change the world, I just wanna punch it up a little" - Joss Whedon
"I don’t think that I can change the world, I just wanna punch it up a little" - Joss Whedon
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Chile’s salmon aquaculture benefits from fallowing – and so too could trout farmers

In Chilean salmonid farmers’ worst nightmares, Piscirickettsia salmonis must be a regular feature. This bacterium causes Salmon Rickettsial Septicaemia (SRS), a highly infectious disease whose symptoms include haemorrhaging, lesions, ulcers, anorexia, and many cases death.

SRS is an epidemic in Chile, costing the salmon aquaculture industry over US $300 million each year. Vaccines have been largely ineffective and antibiotics have given mixed results. Mandatory three-month fallowing, on the other hand, seems to routinely reduce the chance of reinfection.

The underlying principle behind fallowing is fairly straightforward. Net-pen systems commonly used by finfish farmers allow pathogens to spread into the wider environment. Some are carried away by currents, some remain suspended in the water column or on the seafloor under and near the farm. In all cases, they wait for a new host to come close enough for reinfection. Fortunately for the fish, and the farmer, pathogens can’t survive forever without a host – which is where fallowing comes in. Take the hosts away and all the equipment out of the water for disinfection, and the odds of contagion rapidly drop…



This article was written for The Fish Site – please continue to read the article on the link below (and yes, I know the link shows a different title - but I can't change it here)

Feel free to comment!

#Aquaculture #Salmon #SRS #RainbowTrout #Trout #FishFarm 

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Controlling the uncontrollable? Sea lice in salmon aquaculture

I put together an article for The Sustainable Food Trust looking at one of the most controversial issues and hard to solve problems facing salmon aquaculture - sea lice infestations.

The article is open access - take a look and feel free to comment here or on the website itself.

#aquaculture #salmon #sealice

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What the GBRMPA chair DID NOT say about my coral bleaching article

In April 2016 I submitted an article to The Marine Professional – a publication of the Institute of Marine Engineering, Science & Technology (IMarEST) focusing on the mass bleaching event that had hit the Great Barrier Reef at the time. In their September 2016 issue, The Marine Professional featured a comment from a reader, in which he stated that he shared the article with Dr. Russell Reichelt – chair of the Great Barrier Reef Marine Park Authority. The reader alleged that Dr Reichlet told him that the article “contains some accurate things mixed with half truths and alarmism” .

A number of coral reef, marine biology, and climate scientists have been in touch to express their concern about Dr Reichelt’s alleged comments on my article. After liaising with Dr Reichelt’s office*, I am pleased to be able to set the record straight on what he did – or rather did not say.

*I did contact Dr Reichelt directly, but he replied via his office not directly.

After corresponding with Dr Reichelt’s office to determine where the “half truths and alarmism” were in the article, I have been informed that, whilst Dr Reichelt recalls the article being brought to his attention, he never made any such comments about the article. In fact, he hadn’t even seen the article to comment on in the first place. He has since read the piece and agrees that it is factual.

I have not attempted to contact the reader to find outwhere his comment came from.

I've put a copy of the submitted article on my blog (link below). For those who want to see the article after it has been through their editorial process, please see the June 2016 edition of The Marine Professional.

#greatbarrierreef   #coralreefs   #bleaching   #climatechange  

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Addressing Knowledge Gaps for Lumpfish Production

The use of cleaner fish such as lumpfish (Cyclopterus lumpus) to control sea lice in aquaculture is rapidly emerging as an effective alternative to medicinal treatments. However lumpfish are a relatively new species to aquaculture and as a result, there still exists a number of knowledge gaps that need to be filled in order to develop sustainable lumpfish production.

At this years Aquaculture Canada and Cold Harvest 2016 Conference, Paul Howes, aquaculture technical manager at Swansea University’s Centre for Sustainable Aquatic Research (CSAR) explained some of the research being done to bring lumpfish as a sea lice control into reality. I wrote about his talk for The Fish Site. Have a read, and feel free to add any comments

#Aquaculture   #sealice   #lumpfish   #biocontrol  

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Improving Aquaculture Feed Sustainability with Genomics

A few weeks ago I was lucky enough to attend the Aquaculture Canada and Coldwater Harvest 2016 Conference held in Newfoundland. Here is another article I wrote for The Fish Site covering just one of of the great talks that went on at the conference

In terms of sustainability, fish feed remains one of the finfish aquaculture industry’s greatest challenges. To alleviate pressure on wild stocks, there is a growing need for aquaculture to reduce – and ideally eliminate – fish meal and fish oil from carnivorous fish feeds


#Aquaculture   #sustainability   #fish   #fishfeed   #genomics  

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Diversification Key for Canadian Aquaculture

A few weeks ago I was lucky enough to attend the Aquaculture Canada and Coldwater Harvest 2016 Conference held in Newfoundland. Here is an article I wrote covering just one of of the great talks that went on at the conference for The Fish Site

"If Atlantic Canada wants to have a strong aquaculture industry, then they must not “put all [their] eggs into one salmon basket”. This was the key message from Professor Thierry Chopin, University of New Brunswick, when he presented at the Aquaculture Canada and Coldwater Harvest 2016 Conference held in St John’s, Newfoundland, this month


#Aquaculture   #Salmon   #SalmonFarms   #Canada  

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Just keep swimming

This little critter is a limpet. From the photo they may not look like the most exciting of creatures. If you’ve ever been down to the coast and taken a look at them yourself… your opinion may not have changed. They don’t seem to move around a lot, or do a lot. Of course looks can be deceiving. Under that shell is the limpet’s squishy body – and their big, muscular foot which, alongside a pretty amazing adhesive secretion, they use to cling onto rocks and other hard surfaces. Anyone who has ever had a go at trying to get a limpet off a rock knows how good a grip they can have. This fabulous foot isn’t just used to stop them from drying out when the tide leaves them exposed to the air, or keep pesky predators (or nosy humans) at bay. Limpets are grazers, feeding on tiny algae on the surface of rocks with their raspy “tongue” (called a radula). See that empty space behind the limpet in the photo? That’s where it’s been grazing. Once they have grazed an area they need to find more food. That foot gets to work, and along moves the limpet, munching up all the algae in its path. Some limpet species even appear to have a home – a particular crevice that they return to just before the tide will expose them to the air.

But this isn’t a post about how amazing limpets are. This is a post about animal movements in the ocean.. Or at least 3 different types of animal movement. Some of them move a lot further than you think. Yes, even limpets.


Larval life
Lots of marine animals – including limpets – are what we call ‘broadcast spawners’. Basically, males release their sperm and females release their eggs into the water at the same time. When these eggs and sperm meet, they are fertilized. Sometime later, if they haven’t been eaten, little baby limpets – limpet larvae – hatch from the eggs. They don’t look much like the limpets you see on rocks yet. They spend their time in “the plankton” – basically in the water where they eat, try not to get eaten, and if they are lucky growing up a bit more. Eventually the time to settle comes, and they (hopefully) end up on some hard substrate like a rock, where if all goes well, they grow up and look more like the limpets we are used to. Thanks to the ocean – waves, tides, wind, currents, and so forth the fertilized eggs and larvae may very well end up away from where their parents are based. We call this ‘dispersal’. How far they go depends on a range of biological factors (e.g. how long they stay in “the plankton” for) and environmental factors (e.g. how strong the current that they end up in is). One open-access study looking at slipper limpets (Crepidula fornicata) – which despite their name are not ‘true limpets’, found that their larvae were probably travelling over 100 km. Not bad for something that looks like a tiny speck. http://dx.doi.org/10.1007/s10152-006-0033-8

Outgrowing your home
Some species seem to like to use very different habitats during different stages of their lives. Let’s take a couple of coral reef fish found in the Philippines for an example – the one-spot snapper (Lutjanus monostigma) and the dash-and-dot goatfish (Parupeneus barberinus) . Both of these species are broadcast spawners – complete with larvae that ends up in the water column for a bit. Once the larvae have made it through their ‘pelagic larvae’ phase, they end up settling in seagrass beds, and mangroves. Yep – these coral reef fish kids aren’t on coral reefs! Might sound a little daft but we need to think about it from the perspective of being a small, vulnerable, hungry fish. Mangroves and seagrass beds tend to have better hiding places for a tiny fish than coral reefs do. They also tend to have lots of yummy nutrients – a perfect place to eat lots and grow quickly whilst avoiding being eaten yourself*. As the fish get older, their needs change. Those handy hiding places when they were younger might be too small for them to hide in now – or move about freely. They might also need different types of food to keep them going. It’s time to move off to the adult habitat – the coral reef. This process of moving between habitats at different stages of the fishes life is known as ontogenetic migration and is thought to be a way to increase the fishes chance of survival as it grows up. Other species of fish seem to use more than 2 or 3 different habitats. Grunts (Haemulon species) for example apparently first settle in rubble, then head off to seagrass beds. After they move into some mangroves, followed by some rocky area – and finally into coral reefs! This kind of movement does raise an interesting question though… are these coral reef fish really just… coral reef fish?

*some studies have suggested that seagrass bed provides more food and mangroves better shelter for many fish species. There may be some additional movement between these two habitats!

http://dx.doi.org/10.1371/journal.pone.0065735
http://dx.doi.org/10.1371/journal.pone.0114715


Long distance travellers
Varvara is a 9 year old grey whale (Eschrichtius robustus) . Like all grey whales, Varvara travels across huge expanses. But Varvara is a rather special whale. In November 2011, she swam from Sakhalin Island (Russia) to Cabo San Lucas (Baja California, Mexico) – and back again. The round-trip, which took her 172 days, covered a whopping 22,511 kilometres (14,000 miles) – the longest mammal migration ever recorded. It is highly likely that Varvara wasn’t alone in making such a huge journey, but she was the one whose journey was recorded the longest. At around the same time Varvara was fitted with a satellite tag, other grey whales too. Some of those satellite tags fell off, some stopped transmitting after a while.

Whales migrate primarily for two reasons – eating and breeding. Grey whales tend to head into warm, lower latitude waters during the winter months to breed, but head back up north in the summer to feed in cooler waters, which are more productive and thus have more food. Why do they go all the way south to breed? Part of the reason is likely because grey whale calves are born with very little blubber. Birth is those chilly northern waters would likely be extremely unpleasant at best, and fatal at worse. Other reasons include where the grey whales use as nursery grounds – shallow lagoons. It’s thought that these lagoons offer the young whales greater protection from predators than more open waters, and can also help the calves float. Yes really! Remember they lack blubber? Well blubber is essentially fat, and that helps with buoyancy. Low blubber means buoyancy is not that great, and these little critters have to keep on swimming. The lagoons help with this because they tend to have higher concentrations of salt than the ocean – which helps the calves to float. Unfortunately when it’s time to migrate back north, the young whales can face all sorts of predators – particularly orca (killer whales), so the system isn’t entirely predator-proof

http://rsbl.royalsocietypublishing.org/content/11/4/20150071


Image:  A limpet munching its way across a rock.  Credit Flickr/NOAA Photo Library.  Licence (CC BY 2.0)


#science #marinelife #marinebiology #whales #coralreef #fish #molluscs #spatialecology #movementecology #oceans
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Academic slave market resembles the drug gangs
Excellent structural analysis of academia in OECD countries

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Where the wild things roam. Dispersal, connectivity, marine protected areas, and my PhD project

In my last post I mentioned that I am starting a PhD. I promised to tell you a little more about what my research will be looking at, so here we go!

The project outline

My research comes very broadly defined already - the work's raison d'être if you like. Here it is:

"Movement and dispersal connects marine populations, allowing restoration of depleted local populations by immigrants that renew genetic diversity. Although Canada’s Oceans Act prioritizes ‘linking Canada’s network of marine protected areas (MPA)’, connectivity has not weighed significantly in MPA network design in Canada. This study will optimize regional marine connectivity among protected areas in the Atlantic region by determining optimal locations for new MPAs and evaluating how commercially important species would be representative in the entire MPA network. To model species distribution based on larval dispersal, fishery pressure, and climate change, we will use 3-D ocean circulation models. Then, based on metapopulation theory, we will develop novel spatial network algorithms to optimise the number and spatial connectivity between MPAs under current and future scenarios of climate and fishery pressure that may alter larval supply"

Sounds complex? Yep, for me too.

Basically the study is saying, if we think about movement of marine animals, particularly larval (baby) ones, where would we put protection in the ocean? With some exceptions, you don’t tend to find all individuals of a species living in one single place. Instead you will find groups of individuals of the same species - populations - living in different places. These populations don't necessarily exist in isolation, with movement of individuals linking populations that are in different parts of the sea. Sometimes there is a lot of movement, sometimes a little. Sometimes a population will be connected to lots of others, sometimes to only a few. Sometimes animals only move when they are of a certain age.

When we are dealing with populations that are connected together, if we lose one or a few of these populations, you could put the whole lot at risk (not enough babies being produced, genetic diversity drops, and a few other things. I'll explain why these are troublesome in a later post). By thinking about where these populations are, and how they are connected, we could improve the survival chances of animal populations - both now and under future climate change (climate change is important because it will alter where different populations are located, and how they will move around).

Whilst this research focuses on marine protected area networks, the work can be applied to all sorts of different management measures, such as those that relate to fisheries, and even thinking about invasive species (e.g. where they are likely to appear, how many could come). The research will also add to our knowledge about the marine environment and areas of science including (but not limited to) spatial ecology (very broadly, why things are where they are), movement ecology (again very broadly, where things move to, and why), and metapopulation (also very broadly, where individuals or groups of individuals in a population are separated over an area).



The research is part of a larger, Canadian-wide Project

If we want to achieve sustainable use of the ocean, and afford other species some rights and protection, then we can't do it alone. Working together is necessary. What is really nice about this particular piece of research is that is just one piece in a larger puzzle that is the Canadian Healthy Oceans Network.

The Canadian Healthy Oceans Network (CHONe) is a partnership of 15 Canadian universities and several Canadian Federal Government Departments including Fisheries and Oceans (DFO). Yep - that’s a fair few people! The overarching aim is to address the need for scientific guidelines for conservation and sustainable use of marine biodiversity resources. The network projects have two broad but very interlinked themes: (1) Ecosystem characteristics that define the resilience and capacity of Canada’s oceans to recover or respond to management strategies such as Marine protected area networks, closures (e.g. for fishery management), or restoration, and (2) Identification of key stressors (things that "mess" with the environment), including cumulative impacts (e.g. what if we pollute the sea AND the sea gets warmer AND…. ) that alter biodiversity, different natural process, and services (stuff we get from the ocean - like fish to eat). My project falls under the first theme. Because this project is closely tied to DFO, there are also scientific deliverables too. Yep - the science done in this network should directly help Canada take better care of the ocean… hopefully…

Just in case you were thinking there wasn't enough connectivity surrounding my connectivity project, my particular project is connected at a much smaller level in the overall network. There is another PhD candidate working on a similar project but for the Pacific coast of Canada. There is also a Post Doctorate Fellow working on fancy algorithms to help make our models work. I've also secured some scientists from the Federal Government's Department of Fisheries and Oceans on my committee (more on what a committee is and how it works later) from both Atlantic and Pacific Canada, which should hopefully help with ensuring the work is relevant and useful to them.

Image : Canada sits right there at the top, below that white mass (hello Greenland and the Arctic!), and above the United States of America. Look how much ocean surrounds it! The rendering was created with Globe Master Android game. For the globe texture, Whole world - land and oceans composite image was used, created by NASA/Goddard Space Flight Center (public domain). Credit Dan Markeye/Flickr. Licence: CC-BY 3.0
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Where the wild things roam. Dispersal, connectivity, marine protected areas, and my PhD project

In my last post I mentioned that I am starting a PhD. I promised to tell you a little more about what my research will be looking at, so here we go!

The project outline

My research comes very broadly defined already - the work's raison d'être if you like. Here it is:

"Movement and dispersal connects marine populations, allowing restoration of depleted local populations by immigrants that renew genetic diversity. Although Canada’s Oceans Act prioritizes ‘linking Canada’s network of marine protected areas (MPA)’, connectivity has not weighed significantly in MPA network design in Canada. This study will optimize regional marine connectivity among protected areas in the Atlantic region by determining optimal locations for new MPAs and evaluating how commercially important species would be representative in the entire MPA network. To model species distribution based on larval dispersal, fishery pressure, and climate change, we will use 3-D ocean circulation models. Then, based on metapopulation theory, we will develop novel spatial network algorithms to optimise the number and spatial connectivity between MPAs under current and future scenarios of climate and fishery pressure that may alter larval supply"

Sounds complex? Yep, for me too.

Basically the study is saying, if we think about movement of marine animals, particularly larval (baby) ones, where would we put protection in the ocean? With some exceptions, you don’t tend to find all individuals of a species living in one single place. Instead you will find groups of individuals of the same species - populations - living in different places. These populations don't necessarily exist in isolation, with movement of individuals linking populations that are in different parts of the sea. Sometimes there is a lot of movement, sometimes a little. Sometimes a population will be connected to lots of others, sometimes to only a few. Sometimes animals only move when they are of a certain age.

When we are dealing with populations that are connected together, if we lose one or a few of these populations, you could put the whole lot at risk (not enough babies being produced, genetic diversity drops, and a few other things. I'll explain why these are troublesome in a later post). By thinking about where these populations are, and how they are connected, we could improve the survival chances of animal populations - both now and under future climate change (climate change is important because it will alter where different populations are located, and how they will move around).

Whilst this research focuses on marine protected area networks, the work can be applied to all sorts of different management measures, such as those that relate to fisheries, and even thinking about invasive species (e.g. where they are likely to appear, how many could come). The research will also add to our knowledge about the marine environment and areas of science including (but not limited to) spatial ecology (very broadly, why things are where they are), movement ecology (again very broadly, where things move to, and why), and metapopulation (also very broadly, where individuals or groups of individuals in a population are separated over an area).



The research is part of a larger, Canadian-wide Project

If we want to achieve sustainable use of the ocean, and afford other species some rights and protection, then we can't do it alone. Working together is necessary. What is really nice about this particular piece of research is that is just one piece in a larger puzzle that is the Canadian Healthy Oceans Network.

The Canadian Healthy Oceans Network (CHONe) is a partnership of 15 Canadian universities and several Canadian Federal Government Departments including Fisheries and Oceans (DFO). Yep - that’s a fair few people! The overarching aim is to address the need for scientific guidelines for conservation and sustainable use of marine biodiversity resources. The network projects have two broad but very interlinked themes: (1) Ecosystem characteristics that define the resilience and capacity of Canada’s oceans to recover or respond to management strategies such as Marine protected area networks, closures (e.g. for fishery management), or restoration, and (2) Identification of key stressors (things that "mess" with the environment), including cumulative impacts (e.g. what if we pollute the sea AND the sea gets warmer AND…. ) that alter biodiversity, different natural process, and services (stuff we get from the ocean - like fish to eat). My project falls under the first theme. Because this project is closely tied to DFO, there are also scientific deliverables too. Yep - the science done in this network should directly help Canada take better care of the ocean… hopefully…

Just in case you were thinking there wasn't enough connectivity surrounding my connectivity project, my particular project is connected at a much smaller level in the overall network. There is another PhD candidate working on a similar project but for the Pacific coast of Canada. There is also a Post Doctorate Fellow working on fancy algorithms to help make our models work. I've also secured some scientists from the Federal Government's Department of Fisheries and Oceans on my committee (more on what a committee is and how it works later) from both Atlantic and Pacific Canada, which should hopefully help with ensuring the work is relevant and useful to them.

Image : Canada sits right there at the top, below that white mass (hello Greenland and the Arctic!), and above the United States of America. Look how much ocean surrounds it! The rendering was created with Globe Master Android game. For the globe texture, Whole world - land and oceans composite image was used, created by NASA/Goddard Space Flight Center (public domain). Credit Dan Markeye/Flickr. Licence: CC-BY 3.0
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