Showing posts with label Coral. Show all posts
Showing posts with label Coral. Show all posts

Sunday, February 5, 2017

I Love It When You Call Me Big Papa

Whether you love him, hate him, or don't care either way; Barack Obama's presidency ended on January 20th. While the 44th president has had a rough time forming a lasting legacy on many fronts; he's proven himself to be the public lands president. Since taking office in 2009 Obama has set aside more land, and even more relevant to Depth and Taxa, ocean than any president in history.

Obama is basically that kid in school who trashed
the curve for everyone else.
Graph based on National Park Service Data

There's a number of ways that land and sea can protected from exploitation in the US. Areas can be set aside as National Parks; which basically prevents them from use other than research and outdoor recreation. Lands can be established as National Forest; which has a conservation aspect but also allows for some extraction of resources. However both of these designations require action by Congress. Action is not something the 114th Congress was famous for. So if a president believes the people that elected him want lands protected, but can't get congress to do anything, how does he go about it? Enter the Antiquities Act.

In the final years of the 19th century Americans were concerned about the rampant destruction of archaeological sites and ecosystems across the country. In response, Congress created the Antiquities Act to allow important cultural, historical, and scientific places to be protected as National Monuments; without the delay that comes from congressional deliberation. Unsurprisingly, Teddy Roosevelt used the act to set aside more acreage than any president until his fifth-cousin took the job in 1933.

"Hahahaha, just try and outdo me little Frankie. I'm the only 
president  this century that everyone liked." -Teddy Roosevelt

You might expect that Democratic presidents are more likely to use the antiquities act, but the exact same number of Democrats and Republicans have established or enlarged National Monuments. In fact, one of the largest ever national monuments was established by the number two acreage protector, none other than George W. Bush! The Papahānaumokuākea (pronounced: papa-ha-now-mo-ku-ah-kay-ah) National Monument was established in 2006 by president Bush and expanded by over 400,000 square miles in 2016 by president Obama.

Papahānaumokuākea (Or for Notorious B.I.G. fans: Big Papa) hits every mark for the intent of the Antiquities Act. It has important historical sites; like Midway Atoll where the Allies scored a major naval victory in World War II. Culturally important places to indigenous Hawaiians. The northwest islands in the monument are believed to be where spirits are born and return to after death. And major ecologically and scientifically important ecosystems. Shallow and deep water stony coral reefs, breeding grounds for endangered species, islands full of endemic plants and animals, and a sea mount as high as Mount Rainier are all found inside the monument.

If we place Papahānaumokuākea on top of the US it's as long as Idaho to Indiana
and as wide as Montana to central Utah.
Image Courtesy; NOAA

Not only does Papahānaumokuākea represent the ideal of what a national monument should be; the restriction it puts on commercial fishing, but not recreational fishing, comes at an essential time in the health of the ocean. There's a growing consensus that about 30% of the world's seas needs to protected from large-scale fishing if we want to continue to feed humanity with good, healthy protein.

 Currently less than 2% of the ocean is covered by marine protected areas, so there's lots of work to be done. Fortunately we already have some guidelines on what makes for an effective marine protected area. One standard uses what are called NEOLI features to plan and assess successful marine protected areas. NEOLI stands for: "No-Take, Enforcement, Old, Large, and Isolated". If a protected marine site can meet four of those five features it's likely to be successful in promoting biodiversity, and in allowing fisher people to collect better catches with less effort at the edge of the protected zone.

"What's that about catching more fish with less effort!?" -This Hawaiian Monk Seal
Courtesy: Dr. James P. McVey, NOAA Sea Grant Program. (NOAA Photo Library: anim0290) 

Obviously Papahānaumokuākea meets the "large" standard, but how's it do in those other areas? Papahānaumokuākea isn't a no-take zone because recreational and sport fisheries are still able to get permits to use the area. However, the scale of recreational fishing is so small relative to commercial fishing that this represents a potentially huge cutback in the amount of harvest within the monument. And before you get frustrated that small scale commercial fishers will be going out of business there's great news. Research has shown that when areas are protected from fishing, species tend to repopulate the protected area and spill over into fishing sites. The edges of the protected area usually have more numerous, larger, and healthier fish than areas far from any protected zone.

Of course no-take doesn't matter if you don't have strong enforcement. This is where Papahānaumokuākea will probably struggle most to meet the standards for protection. The monument is managed by a partnership between the federal and Hawaiian state governments. Hopefully a strong realtionship between these parties will be able to monitor such a vast area. Thankfully some very cool systems are coming online in the near future to help countries protect their natural resources. The Pew Charitable Trusts have developed an incredibly cool program called: Project Eyes on the Seas that uses satellite images, vessel GPS transponders, and home port data to police marine protected areas for relatively cheap.

       Bad Boys, Bad Boys, What'cha Gonna Do? What'cha Gonna Do,
When They Come Fo' You!?
Courtesy: Tony Hisgett via Wikimedia Commons

Now obviously any newly expanded or created national monument isn't going to be considered "old". However, Papahānaumokuākea meets the last NEOLI standard by being isolated from cities and continents, and so thankfully hasn't historically been heavily impacted by human activities. Because exploitation has been limited, Papahānaumokuākea has many of the features we normally associate with old marine protected areas. In fact, in the deep channels between the islands, atolls, and sea mounts of the Hawaiian chain live black corals that have been growing in the same spot for 4,000 years.

Using the NEOLI standards, it looks like Papahānaumokuākea has the potential to help the ocean recover from our historical transgressions, and to provide for humanity in the future. Good environmental policy is about finding balance; meeting the needs of many while protecting the most vulnerable. The ecosystems that produce the natural resources we need have to be kept intact if they're to continue to provide raw materials, jobs, food, inspiration, and a connection to something larger than ourselves. National Monuments like Papahānaumokuākea are an important part of the land-use mosaic that allows the United States to provide the best life for its citizens.

The incoming administration has expressed a focus on the harvest and materials side of the benefits of the environment. An extractive management style may put places like Papahānaumokuākea at risk of having their protections revoked. Both goat farming hippies and doomsday preppers can agree that people have the right to survive off the land. If we can work to remind everyone that all the materials of our modern lives originated from, and are replenished in, pristine ecosystems; then places like Papahānaumokuākea will have a better chance of remaining unaltered. Let's work together to build a broad coalition of people who know the value of functioning ecosystems.

References:

Roberts, Callum M., Hawkins, Julie P., & Gell Fiona R., "The Role of Marine Reserves in Achieving Sustainable Fisheries", Philosophical Transactions of the Royal Society B, Vol. 360 pg. 123-132, 2008.

Bruckner, Andrew, De Angelis, Patricia, & Montgomery, Tony, "Case Study for Black Coral From Hawaii", Non-Detriment Findings Case Studies, WG 9- Aquatic Invertebrates, Case Study 1, Meeting of the IUCN 2008. 
Accessed via: http://www.conabio.gob.mx/institucion/cooperacion_internacional/TallerNDF/Links-Documentos/WG-CS/WG9-AquaticInvertebrates/WG9-CS1%20BlackCoral/WG9-CS1.pdf

Edgar et Al. "Global Conservation Outcomes Depend on Marine Protected Areas with Five Key Features", Nature, Vol. 506, Pg. 216-229, Feb. 13th 2014.
Accessed via: http://www.nature.com/nature/journal/v506/n7487/full/nature13022.html

Long, Tony, "How Satellite Monitoring is Helping Catch Bad Actors", Pew Charitable Trusts Research & Analysis Online, March 7th 2016.
Accessed via: http://www.pewtrusts.org/en/research-and-analysis/analysis/2016/03/03/how-satellite-monitoring-is-helping-catch-bad-actors

US Congress, "American Antiquities Act of 1906"
Accessed via: https://www.nps.gov/history/local-law/anti1906.htm

Sunday, October 19, 2014

Underwater Basket Weaving

Hey everyone, this week we're diving into a bit of a mystery. There's a pretty good chance that by now this little gem has come across your social media feed!


The original of that video had 8 million views on facebook alone last I checked. I've gotta say it's really cool that people are so curious about ocean animals. But the question on everyone's mind seems to be, as my mom succinctly put it: "What the heck is it?" Despite its facehuggerly appearance this is a native of the earth, or should I say the sea? What you're looking is a basket star. I should also mention that I'm not the first to identify this guy/gal. Both the Echinoblog, and IFLScience have tackled this mystery.

First off basket stars aren't actually a true sea star. You may remember from the post on catch connective tissue that sea stars are members of the echinoderm phylum. More specifically the sea stars we're most familiar with make up the asteroidea class (a class is one grouping more specific than a phylum) So if you're feeling pedantic and mischievous you can tell people you found tons of asteroids on the beach and not be lying. However the basket star is not an asteroid! Basket stars are part of a class of animals called ophiuroids (pronounced "off-yer-roids), and are more commonly called brittle stars.

 Jazz Hands!
Courtesy  Paul Thompson via Flickr


Even though most brittle stars look quite a bit like traditional sea stars, being in a separate class means they are as different from a true sea star as a sea urchin is. One of the most notable differences between sea stars and brittle stars is in how they get around. Sea stars use their hundreds of suction cup tube feet to grip tightly to the bottom and cruise along. Their rays (also referred to as arms) act as more of a platform for those strong tube feet to operate from. Brittle stars don't use their tube feet to walk. Instead they pick themselves up on their rays and stroll or slither like something out of the Nightmare before Christmas. Their tube feet lack suction cups and are used to grab food and help move it towards their mouth.


Basket stars are a really cool specialized group of brittle stars. They are well adapted for collecting plankton out of the water with their arms. In the above video you can only catch the view for a second, but at one point the basket star opens all its arms, and you can see the central disk. The disk is pentagonal and one trunk-like arm grows out of each side. Each of those five arms then branches dozens of times to create a wide net. The arms of the basket star are covered in microscopic hooks, a nice coating of mucus, and are capable of coiling around themselves to form traps that hold onto their planktonic prey. Below you can watch as some euphasiid shrimp are added to a basket star's tank at the Seattle Aquarium.


That video is a little sped up, but you can see how those branches form a wide net and are waved back and forth to sweep for more food. Grabbing food out of the water like this is called suspension feeding. Sometimes you'll hear it called filter feeding, but that's a bit different. When there isn't an obvious load of plankton around them, basket stars usually cling to a hard surface or the branches of corals. They curl their rays up above their bodies into the current forming a basket shape. Hence the name.

What a basket ca...I'm not even gonna let myself finish that joke
By Peter Southwood (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons


Once a basket star has enough food trapped on one of their rays they'll slowly move it towards their star shaped mouth. Incidentally brittle stars don't have an anus, so they excrete their waste through the same hole they consume food. Anyway inside the mouth are five sets of comb-like teeth. The star slides its arms over the teeth and the prey are scraped off like frosting from a fork. Am I the only one who does that? I can't be the only one who does that.


Basket stars are found throughout the world from shallow water to the abyssal plane. The one from the original video is probably Euryale aspera which is a shallow living basket star found throughout the Indian ocean and tropical western Pacific. One of the things I think is coolest about basket stars is that they seem to have a strong association with a variety of coral species. Not only do coral branches make a good holding place for adult basket stars, they may even be an important nursery for juveniles. Young of the species most commonly found around N. America, Gorgonocephalus eucnemis, are usually found living just inside the polyps of the sea strawberry coral (Gersemia spp.). While this seems to be some type of symbiotic relationship, it isn't entirely clear if the little basket stars are stealing food from the polyp they're living on, or just using their mouth as a platform to feed from.

References:


Stöhr, S., O’hara, T., & Thuy, B. (March 2nd 2012) “Global Diversity of Brittle Stars (Echinodermata: Ophiuroidea)” PLOS ONE DOI: 10.1371/journal.pone.0031940,
Accessed via http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0031940

"What is that weird thing on facebook???" The Echinoblog
http://echinoblog.blogspot.com/2014/10/what-is-that-weird-thing-on-facebook.html

Gorgonocephalus eucnemis” Encyclopedia of Life, 
http://eol.org/pages/599654/details

"Gersemia” Encyclopedia of Life, 

Sunday, September 28, 2014

Getting Ston(ey)ed with Coral

We're Back! The new Depth and Taxa headquarters (AKA my apartment) is all set up with a fancy desk and everything. Thanks everyone for your patience during my moving process. So without further ado let's get back in the swing of things.

There was some great news that came out of the US National Oceanographic and Atmospheric Administration (NOAA) last month. Twenty coral species have been listed under the Endangered Species Act. "What? That's horrible, more corals are at risk of extinction!" you might be saying, but listing as endangered actually benefits many animals that are at the brink. When organisms are imperiled by extinction listing them serves to provide legal protections for, not only them, but also their ecosystems. It's kind of like a silent alarm going off. When someone breaks in, property is at risk, but once the alarm goes off; the police can come and take steps to keep you from being burgled. It's about time we got serious about protecting coral too. Whole reefs are in danger of disappearing. One study suggests that coral cover in the region between Asia, Australia and Hawaii has decreased by 20% since just the early eighties.

So why do we care? Coral is certainly very pretty, but it's also a fascinating and essential organism.

Seen here being all three at once.
Courtesy Ian Robertson via Flickr

Coral is a massive and incredibly old group of animals. In fact just about anything you think of as ancient, corals were there for its beginning: Megalodon? Coral bemoans its short time on the planet. Dinosaurs? Yeah coral thought they were cool for a while. Coelocanths? They're just trying to steal coral's old-timey charm. What I'm getting at is that coral shows up very early in the fossil record, something like 480 million years ago!

So what's the secret to coral's success? Well diversity is a big part of it. There are something like 2,500 coral species on earth today. They can be hard, soft, individual, colonial, small, large, tropical, temperate, shallow, and deep.  The corals we're most familiar with, and all of those recently added to the endangered species list, are the shallow-living stony corals we like to brag about snorkeling among when we take a trip to the tropics.

All corals are a part of the cnidarian phylum which you may remember from the earlier post about jellyfish.You might also remember that the scyphozoa, hydrozoa, and cubozoa have two life stages: the free-living medusa and the stuck-on polyp. Corals are part of the anthozoa which are all the animals that have no medusa stage.

Perseus can get behind an animal that removes the medusa. (I will not apologize for this terrible joke)
Courtesy Wally Gobetz via Flickr

What stands stony corals out from other members of their phylum is their structure. Unlike sea anemones or jellies; stony corals actually secrete a skeleton. Coral that you might find at a jeweler's, or on the beach, is in fact the skeletal remains of a stony coral. So your beach house may have skeletons in its closet as well as on its coffee table. These skeletons, made of the same molecules as eggshells, are what allow for the gigantic reefs seen in tropical waters throughout the world. And amazingly every reef starts out as a single teeny-tiny coral polyp.

See when a coral mommy-daddy and daddy-mommy (many stony corals are hermaphroditic) love each other very much, and the season and tidal phase are right, they pour floating packets of sperm and eggs out of their bodies and into the water. It's all very romantic as thousands of other animals circle the waters around them devouring their genetic material before it even has a chance to mix. But luckily there are so many of these gamete (reproductive cells) balloons that some do make a new baby coral. At this point in their life baby corals are called a planula, they're microscopic, and they're covered in little cellular oars that allow them to move and find a place to settle. As they settle, baby coral metamorphoses into its adult form, but its still incredibly tiny and all alone. So our intrepid hero begins making itself some friends, by cloning.

"I'm pleased...we're pleased...it's nice to meet you"
Courtesy Nhobgood via Wikimedia Commons

Each of those little anemone looking things up there is a clone of a single polyp that settled on a hard surface. If the entire colony is very large, then the original polyp probably settled decades ago. Some head's of coral have been estimated to be over a thousand years old! This slow growth rate is one of the reasons many coral reefs are at risk of extinction.

 Amazingly, although the clones are separate individuals from the other polyps they all share body tissues with one another. As the polyps catch prey with their stinging tentacles and eat it; the nutrients from that food are actually spread across the shared tissue so that the whole colony benefits. These shared tissues are also what secrete the hard skeleton of stony corals. And it's inside the corals' shared tissues that we can find the reason for their stony skeleton.

Just beneath the skin of stony corals lives one of a number of different algae. These single-celled seaweeds, called zooxanthellae, (pronounced zo-zan-thell-ee) are taken in by the coral deliberately because they can benefit one another greatly. The algae is protected from the thousands of mouths out in the plankton and the corals' wastes make great fertilizer. The coral also benefits because the algae's photosynthesis provides oxygen and nutrients both of which the coral can use. So the coral creates this elaborate skeleton in part to reach for the sun. The skeleton acts like the trunk and branches of a tree pushing the coral and its algae buddies towards the light. The constant competition for sun is what has driven the evolution of so many amazing forms and shapes of different corals.

Enough sun salutes to make a yogi weep for joy
Courtesy US Fish and Wildlife via Flickr

 This mutual symbiosis has been going on for so long and is so beneficial that some coral species can't feed themselves without their zooxanthellae. When people talk about coral bleaching this is what they mean. Something has gone wrong in the ecosystem, so the algae have either gone elsewhere or died. Leaving only skeletons behind. Luckily you can easily help prevent bleaching if you visit tropical areas. Danovaro et. al discovered that synthetic sunscreens actually encourage the growth of viruses that infect and kill zooxanthellae. So when you take that snorkeling trip make sure to use non-synthetics like titanium dioxide or zinc oxide. Often times these sunscreens are labeled as "coral safe" or "sensitive skin" so they're easily found.

References:

http://www.fws.gov/endangered/laws-policies/

http://www.noaanews.noaa.gov/stories2014/20140827_corallisting.html

http://www.ucmp.berkeley.edu/cnidaria/anthozoafr.html

https://marine.rutgers.edu/pubs/private/Mass%20et%20al_Immunolocalization_PNAS2014.full.pdf

Danovaro et. al, "Sunscreens Cause Coral Bleaching by Promoting Viral Infections", Environmental Heatlth Perspectives Apr. 2008: 116(14): 441-447. Accessed via http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2291018/

Hoover, John P. "Hawai'i's Sea Creatures: A Guide to Hawai'i's Marine Invertebrates", pg 46-49, Mutual Publishing, 1999