Thursday, November 13, 2014

Giving Turtles a Head Start

*Guest post by Jethro Valido -one of several posts selected from the graduate EES3001 Scientific Literacy course at University of Toronto-Scarborough.


Photo from  Adopt-a-Pond at Toronto Zoo
When I think about turtles, the first things to come to mind are that they are slow and that they’ve been on Earth for forever. So it came to me as a surprise when I found out that most of Ontario’s turtles are actually endangered and at risk of disappearing in Ontario. In fact, seven out of the eight turtle species found in Ontario are threatened
and are in dire need of help in order to maintain populations. The problem with turtles are that they are extremely long-lived (can live up to 70+ years) and that they have a late sexual maturation (20-25 years). This makes it hard for us to study them and pin-point a cause to their decline, especially when action is required immediately.

So what exactly can we do to help their numbers from declining? One way we can help our turtles is through a head-start program. A head-start program is the process in which juveniles (in this case turtle eggs) are raised in captivity until they reach a certain age, and then they are release back into the wild. This is exactly what I am doing at the Toronto zoo; where we are head-starting the Blanding’s turtle.

The Blanding’s Turtle is one of the threatened species of turtles in Ontario. It can be easily identified and differentiated from other native turtles by its yellow throat and jaw. The biggest threats to this species are associated with humans; ranging from habitat loss due to land development, to being hit by cars when trying to cross roads due to habitat fragmentation, to predation from urban wildlife, such as raccoons, coyotes, skunks, etc. Though once numerous, their numbers have drastically declined, and to help restore their numbers, we are implementing a head-start program for this species at the zoo. This will help encourage the young to grow to maturity, where they have a higher success rate at surviving than when juveniles.

Photo from  Adopt-a-Pond at Toronto Zoo
The head-start program starts off with looking for Blanding’s turtle nests in at-risk locations. These locations are areas such as crop fields, where the eggs they would not have a good chance for survival. These eggs are then transported to the Toronto zoo where they are raised in captivity until they are 2 years old. The reason for this is to prevent predation. At birth, the turtles are very small and are easy prey for animals such as raccoons. By raising them until they are 2 in what could be called a “safe haven” for the turtles, they can grow to a sufficient size to deter predation once released. By deterring predation, their chances for survival is increased.  Once released, the turtles are tracked by radio-tracking devices and monitored.

The really interesting part about this all as a research student working at the Toronto zoo, is that there a lot of questions around the idea and process of head-starting. Although head-starting has been successful for sea turtles, its success is unknown for these freshwater turtles we have in Ontario; including Blanding’s turtle. The Toronto zoo is invested in this project long term, especially since the Blanding’s turtle has a late maturation, thus this project will be heavily research-based to understand the effects head-starting has on these turtles and whether the protocols are well-suited for the turtles. Because of this, there is a huge range of flexibility in adjusting or improving protocols and it is really something that can be applied to other turtle species around the world.

Photo from  Adopt-a-Pond at Toronto Zoo
The Adopt-a-Pond Program at the Toronto zoo is heavily involved with this project and they are quite determined to restore our Blanding’s turtle populations. With the release of these two year old turtles, Adopt-a-Pond is as well restoring their habitat; wetlands. Not only will these turtles receive help but they will act as an umbrella species to protect other threatened wetland species as well. Though we are not 100% certain whether head-starting will restore the Blanding’s turtle populations, this project is just a step in aiding declining turtle populations. From this, hopefully we can gain and discover answers to many of the questions concerning its decline, and eventually manage a long-term solution. Though rare today, hopefully one day, I can walk around the Rouge Park and bump into a yellow-throated turtle.



Here are some additional links:
-       Adopt-a-Pond Blog http://adoptapond.wordpress.com/ - Here, you can follow the Adopt-a-Pond team on their blog. They post up plenty of blogs following the status of their turtles (including Blanding’s turtles) and their releases
-       Earth Rangers Blog http://www.earthrangers.org/blog/ - Here, you can follow the Earth Rangers blog (Earth Rangers are in partnership to head-start the Blanding’s turtle). The website is mostly for children but they have posted up head-starting blogs. 

Tuesday, November 11, 2014

Could today’s oil rigs be tomorrow’s biodiversity hotspots?

*Guest post by Bryan Flood -one of several posts selected from the graduate EES3001 Scientific Literacy course at University of Toronto-Scarborough.

ResearchBlogging.orgNew research by Jeremy Claisse and colleagues at Occidental College in Los Angles have discovered that secondary fish production at oil and gas platforms off the coast of California is up to an order of magnitude higher than other marine ecosystems. This includes reefs and estuaries, normally considered some of the most productive ecosystems on the planet.

Photo from: US Bureau of Ocean Energy Management - http://www.data.boem.gov/homepg/data_center/other/imagecate/imageview.asp?ID=292
The authors measured the total productivity at oil and gas platforms and divided by the platform’s footprint to get a per-square-metre productivity. Herein lies the secret: The authors attribute these phenomenal productivities to the large hardscape (physical surfaces of the rigs) to seafloor ratio.

Having a structure that spans the total water column creates a range of habitats for a diverse variety of species and life stages, as well as creating a complex structure with large surface area which translates directly into habitat. This habitat attracts many species including rockfish larvae, invertebrates and planktonic food resources. These form the base of the food web, subsequently attracting adult fish and other organisms.

These results have important implications for the future of the more than 7500 oil and gas platforms around the world that will need to be decommissioned at the end of their service life. Should they be dismantled, or left as artificial reefs? Should future platforms and wind turbines be designed with an afterlife as an artificial reef in mind? Could these structures one day dot the seas with aquatic metropolises?


Claisse, J., Pondella, D., Love, M., Zahn, L., Williams, C., Williams, J., & Bull, A. (2014). Oil platforms off California are among the most productive marine fish habitats globally Proceedings of the National Academy of Sciences, 111 (43), 15462-15467 DOI: 10.1073/pnas.1411477111

Monday, November 10, 2014

To Keep Invasive Asian Carp from the Great Lakes, Carp Catchers Get Creative

*Guest post by Noemie De Vuyst -one of several posts selected from the graduate EES3001 Scientific Literacy course at University of Toronto-Scarborough.

Some say fishing is a peaceful pursuit. Not so if you're one of the self-dubbed Carp-Hunters, a pair of Illinois fishing guides whose carp-catching antics have turned them into YouTube celebrities. Over the last three years, videos of their over-the-top methods have racked up hundreds of thousands of views.

They've netted carp while on water-skis, and speared them with samurai swords and costume Wolverine claws. In Illinois' rivers, the Asian carp are so abundant they practically jump into the outstretched nets themselves. In an ecosystem where the invasive species has largely displaced native fish, the Carp-Hunters’ new hobby has a higher purpose; “We care greatly about preserving out natural ecosystem”, their video’s intro reads. “Since we can’t bass fish anymore we have taken on this burden.”




Silver Carp in the Illinois River, 2009. Nerissa Michaels/Illinois River Biological Station, via Detroit Free Press. 

Kooky as their methods may be, the Carp-Hunters have something in common with government agencies on either side of the Great Lakes; they're both battling the highly invasive Asian carp.
Though the U.S. and Canadian officials may not be going after the invaders with the same flair – not everybody gets to name their fishing boat the “Carpocalypse” - they've been labouring to keep the fish out of the Great Lakes since escapees from fish farms were discovered in the 1990's. With their enormous appetites and extraordinary ability to reproduce at speed, Asian carp would be disastrous to ecosystems and economies if they ever reached the Great Lakes.

First brought to North America in the 1970's, Asian carp already dominate some US waterways. The town of Havana, Illinois, just 85km downstream of Carp-Hunters fishing grounds, is thought to have one of the highest abundances of Asian carp on Earth. Here, the carp make up 60% of the fish community.

The uphill battle to keep carp from the Great Lakes has popped up in the news recently. In early October, the routine testing of 200 sites found a single sample of silver carp environmental DNA (or eDNA) in the Kalamazoo River, a tributary to Lake Michigan.

What does it mean that this one sample tested positive? The presence of eDNA shows only that silver carp material was present at the site. What it can't tell us is whether the carp was alive, or how many fish there might have been. In fact, the presence of eDNA doesn't tell us that a silver carp was present at the site at all; it's possible that scales or tiny amounts of mucous were transported by boats or fishing equipment, or even in bird droppings. With no silver carp sightings in the Kalamazoo, it seems likely the positive result comes from one of these explanations.

Despite the low likelihood that silver carp had really spread to the Great Lakes, news of the positive eDNA result was quickly picked by many local news outlets. Within days, the US Fish and Wildlife Service sped through the collection and testing of 200 more samples, and appealed to anglers to report any carp sightings.

Why such a quick response for a finding with such high uncertainty? If Asian carp were to spread to the Great Lakes, it's feared they take over aquatic ecosystems and cause the fishing and angling industries millions of dollars of loss. Silver carp are especially worrisome, since they have a taste for the same microorganisms and algae that many native species rely on.

By late October, the results of Michigan's second batch of eDNA testing were announced; all samples were negative. For now, it seems the silver carp have crept no closer to the Great Lakes watershed. Canada and the US continue to monitor their waterways closely and to put in new measures to prevent the spread of the fish. This past July, Fisheries and Oceans Canada opened a new Asian Carp Science Lab. In a political climate that has squeezed environmental sciences from all sides, the funding of a new facility highlights the carps' immense potential to cause damage.

So even with their home-built contraptions, it looks like Illinois’ Carp-Catchers are doing their bit for the Great Lakes.


  
For more information on eDNA sampling at the Michigan Department of Natural Resources:
http://www.michigan.gov/dnr/0,4570,7-153--340230--rss,00.html
http://www.asiancarp.us/edna.htm

For details on the new Asian Carp Lab at Fisheries and Oceans Canada:
http://news.gc.ca/web/article-en.do?nid=865809

And to see those Carp-Hunters do their thing:

https://www.youtube.com/watch?v=hN2gMP3Q2Z4