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Wednesday, December 30, 2015

An Eventful Echinoblog in 2015! #Recap!

So, I don't normally do these "end of the year" recaps, but man, 2015 was BUSY.  I travelled to three continents, described a NEW FAMILY of starfish in addition to all the other stuff.. Here are highlights....


1. JAPAN part TWO! 
Starting at the end of January I returned to study at Japan's world famous National Museum of Nature and Science in Tsukuba, Japan (outside Tokyo). Among the many cool adventures:



One such interesting starfish was Trophodiscus! The starfish which broods babies on the disk surface! 
2. Someone made one of my starfish into a TOY! 

A video of the set is here.. My contribution is at the end..

3. I described a NEW FAMILY, genus and two new species of sea stars! The first hydrothermal starfish Paulasterias


Named for deep-sea biologist Paul Tyler, the type species is the first to be found living in association with hydrothermal vent habitats.
The second species, occurs in the North Pacific and is named for my colleague Dr. Craig McClain at Deep-Sea News and was collected during an expedition which I was present on due to Craig's invitation! Scientific collaboration in action! 


4. I visited and have studied at the Iziko Museum in Cape Town South Africa!

One of my most memorable trips was from April-May when I visited the Iziko Museum in Cape Town, South Africa!! Thanks to a collaboration with Dr. Lara Atkinson from their marine environmental organization, SAEON (the South African Environmental Observation Network) I was able to visit their marine invertebrates collection and study the collections.

This was a VERY frutiful visit. I identified nearly 700 specimens, and discovered several rarely seen species as well as working with the the citizen science community to ID species seen by divers and naturalists.


Here were some images from the trip... one of the South African Museum's specimen catalogs and Candice one of the curatorial techs holding a specimen of Hymenaster! A specimen of a deep-sea slime star which had been sitting undiscovered for some 40 years! 


My thanks to Lara and the staff at the Iziko Museum including curator Wayne Florence and collections personnel Liz and Candice for a GREAT visit! 

5. Described new Deep-sea starfish which feed on corals
So, I described several new species this year..but for some reason a bunch of them feed on deep-sea corals.. Here's a post where I talk about a new paper describing new Hawaiian species.. Some of which I saw later on when Okeanos investigated the Hawaiian Islands!
                            

6. I provided my usual narrative and information to Okeanos Explorer in Puerto Rico and Hawaii! 
For the last few years I've participated as part of the "shoreside" talent pool which Okeanos calls upon to assist with identifications and questions about sea stars and echinoderms. 

I also take screengrabs of the live feed and post highlights. This year, Okeanos travelled from the tropical Atlantic, working off Puerto Rico, travelling across the canal to the North Pacific where they worked in the Hawaiian Islands!!

Perhaps one of my proudest moments from the Puerto Rican expedition was being able to identify this rarely seen solasterid starfish, Laetmaster spectabilis from the abyss of the tropical Atlantic!

This species had been collected once in the 19th Century and not been seen again until the Okeanos Oceano Profundo expedition! Here's a recap post from that week. 

When Okeanos Explorer reached the Hawaiian Islands we saw some species that I described back in 2006. This for example, was Circeaster arandae, which was known originally from Madagascar and New Caledonia. Now we know it lives in the Hawaiian Islands! 

Its a weird feeling to have described something like this from preserved specimens and then to seem them alive like this..
and we saw some weird critters like this, which were probably new but remained a mystery...

We also saw a LOT of glass sponges.(go here)

Stalked crinoids, benthic ctenophores and enormous sponges! (go here)


7. Took a little break for the first INTERNATIONAL POLYCHAETE DAY! on July 1st! 
In honor of Dr. Kristian Fauchald, curator of polychaete worms at the Smithsonian's NMNH, who passed away on April 5, 2015. This year we celebrated the very first International Polychaete Day on Kristian's birthday. 
Polychaete worm
Here is the Storify if you missed it! 

8. Then I helped launch SEA SLUG DAY!! 
This event was similar to International Polychaete Day except that it celebrated the very much alive, Dr. Terry Gosliner at the California Academy of Sciences. The world's foremost authority on nudibranchs and their kin.  Sea Slug Day was appropriately enough held on October 29th, his brithday the Friday before Halloween! 
Goniobranchus roboi
Here is the Storify if you missed it! 

9. Studied Deep-sea Starfish at the Paris Museum in November! 
I've been visiting Paris for several years now and so, the trip has become almost routine. I'm usually there for about a month working on new species from exotic Pacific and Indian Ocean locales collected by French museum scientists.

I even worked some Cretaceous (fossil) starfish into the visit this time around. Hopefully by next year you will be seeing some of the new species published and publicized here!

10. And last but not least.. I topped 3000 Twitter followers! My thanks to all of you!!
My ongoing efforts at education and outreach would not be possible without YOU!!! 
Its good to know that what I produce is read and of interest. Twitter has given me a more regular way to share..but the blog remains appropriate for "long form" stories...

Thanks to everyone who follows! 

For those who are interested, I actually try to keep track of my new species on this post. It shows images of each! (its a little behind at the moment..but soon!)

Thursday, December 24, 2015

Happy Holidays! Protoreaster lincki! A festively colored tropical Indian Ocean starfish for your winter solstice!

Image taken by Jan Mees. From the World Registry of Marine Species
This week, a photoessay and odd little facts about this very strikingly colored/decorated oreasterid starfish, Protoreaster lincki!  You can check this past post on how to tell Protoreaster species from the similar Pentaceraster species..

This is a shallow-water tropical species known primarily from the western Indian Ocean, especially on the east African coast. The species descriptor "lincki" is named for the German naturalist Johann Heinrich Linck, the author of a noted monograph on sea stars, De stellis marinis liber singularis published in 1733. Johann Linck is also the namesake of the familiar starfish genus Linckia. Many years ago I wrote a little bit about where funky starfish names come from before, especially Nardoa and Luidia.
We really don't know much about the primary biology of this species. Its thought that they feed primarily on microalgal film so presumably they are dependent on the "goo" on sea grass, sea bottoms, etc.  

This species is fairly easy to recognize due to its striking red on white coloration, but also the very distinctive pattern of spines and etc... There is some variation however. Spines in some individuals are more conical versus others which are more blunt...
Image taken by Adrian Pingstone 2005 at Bristol Zoo Aquarium, Bristol, England via Wikipedia

red starfish
Close up of Starfish (Protoreaster linckii), Kenya.
red-knobbed starfish (Protoreaster linckii)
Red, yellow, and grey starfish
Zanzibar Starfish
The spines on this species and other oreasterid starfish likely serve against larger predators. Its unclear if they are effective against smaller specialized echinoderm predators such as these harlequin shrimp

Variation! The skeletal patterns on these sea stars are broadly consistent and distinctive for this species. But in the same way that people can have different hair and skin color, different facial features, etc. starfish show variation in spination, pattern and even color... 

Here are some examples. Its unclear if the differences are simply random or if they correspond to some kind of environmental factor such as food, etc.

Mozambique
Red-knobbed star

Tanzania, African coast.
DSCN3193
Tanzania, African coast.
Red-knobbed Starfish
Tanzania, African coast
Tanzania March 2009 261
Zanzibar, African coast
Zanzibar 2005 192 (Large)
and the occasional 6 armed variant..
Red star on the beach

As with the Indo-Pacific species, P. nodosus, this species is fished for the tourist trade. Data about its reproductive abilities and "carrying capacity" for a fishery aren't well documented.
StarfishStarfish flashers

ART! For some odd reason, this species has also served as the inspiration for many distinct types of art. This postage stamp...for Mozambique in 1982 and the more recent rendition below it, including the pastel and of course TATTOOS! 
via the World Registry of Marine Species


Starfish by CreativeCurseKina on DeviantArt

starfish tattoo by SunofKyuss on DeviantArt

Happy Holidays from the Echinoblog!

Wednesday, December 9, 2015

What's up with dead starfish washed up on beaches?


So, for whatever reason, I've been noticing an uptick in the number of reports (and questions from the public) about moribund or otherwise dead starfishes (aka sea stars) being washed up on beaches en masse. 
to this account of Asterias rubens  from Pensam Beach, New North Wales in the UK,


And I've seen a host of different reports. Many from the southeast coast of the United States, in the United Kingdom and even from Cape Town, South Africa. 

I thought I would take a moment to provide what seems to be the MOST likely explanation: During storms, violent or strong water currents pick starfish up off soft sediment bottoms and wash them ashore.

Different species of starfish in different parts of the world are affected but all share certain commonalities.
Dead starfish at Budleigh Salterton March 2010
So here's the thing. As a scientist I've NOT actually seen storm-driven currents pick up hundreds to thousands of starfish and drop them on the beach. My conclusion is based on an assessment of various environmental factors which all point to, what seems to me, a parsimonious conclusion.

You'll often see a lot of officials and local biologists essentially say the same thing. There are LOTS of these starfish present AFTER a storm. 

None of them actually saw what happened (and how could they have?) but this seems like an explanation which fits all the facts. 

Lines of reasoning and evidence pointing to the "storms beach starfish" hypothesis
  • In almost EVERY instance that this has been reported, there have been reports of either storms or high winds. Even if this was not necessarily reported in the news report itself. For example in the case of the Queensland Pentaceraster case, there was a reported storm involving hail the day before!(here
  • Bear in mind that storms don't JUST mean high winds and rough water current. It also means FRESH WATER input. Echinoderms are notoriously intolerant of low salinity/freshwater. Low salinity water might serve to weaken or otherwise just disable enough of them to be washed ashore. 
  • The species in question: Luidia clathrata, Pentaceraster sp., Asterias forbesi, Asterias rubens etc. (and others) are all known to occur on sandy or unconsolidated (i.e. loose sand) sediment bottoms. So its not unreasonable to see how strong water currents associated with inclement weather could serve to pick them up and drop them ashore. These species all tend to occur with rather high abundance so they tend to end up washed ashore in great numbers.
Some Common questions:

1. There are SO many dead! Will the starfish population recover?
     Yes. Almost certainly. Although it seems like hundreds to thousands of individuals bear in mind that many of these species occur over a huge area (Luidia clathrata for example occurs throughout the Gulf of Mexico and along the southeastern coast of the United States) and their spawn includes hundreds of millions of individuals.
     A related question to this usually involves "If they survive, shouldn't they be put back?" Unfortunately, its unlikely that most of them have survived by the time they've been found. Would it be good to have them returned to the ocean? Sure. And in fact, the good folks in Fish Hoek Beach in Cape Town, South Africa did just that!! 
The living starfish  (species: Marthasterias glacialis) were collected and returned to the ocean. From an ecological/population ecology perspective this was probably a trivial event but it says a lot about the people involved. So good on them! 

2. Based on the news articles, scientists are always BAFFLED! BAFFLED I tells ya'! About this "starfish washing up thing" Why is that??
So, uh... scientists are not REALLY baffled by these events. Almost every article about starfish washing up on a beach usually involves a scientist providing an explanation for what happened. Usually involving a storm or freshwater input. But as I said before none of them (myself included) actually SAW what happened. And so their explanation is usually filled with qualifiers and caveats that the news media exploits as "SCIENTISTS BAFFLED BY THIS THING THAT HAPPENED!" 
and of course, there is a.. how shall we say... "sensationalist" element which is used to make the story a bit more appealing to the general populace. 

But really? It was probably storms stranding them on the beach. 

3. OH NOES! We recently read about whales/dolphins/jellyfishes being stranded on the beach!! Does this mean the starfish are all dying and beaching themselves on the beach for the same reason??? 

*sigh* No. No it does not.

Animals such as whales, dolphins and jellies (jellyfish) all swim in the water column. In the case of animals like jellyfish and/or by the wind-sailors, water currents end up carrying a bunch of them onshore. Its not always clear what beaches whales and dolphins (or if there is a single reason in every case) but in these cases, we have animals that are in constant motion that get stranded based in part on the animals getting there on their own power.  

Starfish live on the ocean bottom. They get picked up and carried to the beach. Its a localized event tied to something specific..like a storm. It would have to be VERY unusual to see some kind of event that would be the sole cause of mortality affecting constantly swimming (i.e., pelagic) animals like dolphins and bottom living invertebrates like sea stars.

4. OH NOES! ITS TEH STARFISH WASTING DISEASE!! 

Nope. When starfish succumb to starfish wasting disease (aka starfish wasting syndrome, etc.) they show white lesions and in most cases they disintegrate in place, whether its underwater or in the intertidal or wherever. Image from the UCSC Starfish Wasting Disease Page.

Currently, Starfish Wasting seems to be primarily centered on the west coast of North America.


Most of the animals one observes washed up on the beach generally seem to have been in good health.  
Dead starfish at Budleigh Salterton March 2010
Dead starfish at Budleigh Salterton March 2010

Is it possible that infected starfish could begin to appear? Sure. But individuals would need to show lesions or other indications of disease which we have yet to observe. 

5. OH NOES! ITS TEH End of Days/R'Lyeh is rising and Cthulhu is chasing the starfish out of the sea!!
                           
If Cthulhu's return caused a massive storm surge, with high velocity wind and water currents and huge storms causing freshwater input to local ecosystems thus resulting in a big low-salinity wave that washed a bunch of starfish onto shore? then... maybe. But otherwise. no. 

But seriously.. do I continue to be interested in beachings? Sure. Many interesting potential questions. Are we seeing more of these beachings because of climate change-related storms? How seriously do these storms affect the populations of these species? and more importantly their prey? How regularly do they occur?   But let's keep them to normal, localized phenomena and not crazy, "end of the world" death storm events shall we?? 

Monday, November 30, 2015

Imaging Brooding Brittle Stars Babies!

Greetings! So, today I am en transit from my month long research trip in Paris back to home base in Washington DC!  So, in the meantime I thought I would share the results of this great new imaging project presented in GigaScience by some colleagues at CapeTown University in South Africa whom I met while I was visiting a few months ago!!  Jannes Landschoff, Anton duPlessis and Charlie Griffiths.

Their study actually surveys THREE species of brooding brittle stars!

What does this mean? In MOST echinoderms,  following fertilization juveniles pretty much settle out on their own and are left to grow/rear out on their own. But in some unusual instances there is actually parental care! 

So, yes, some adult echinoderms rear juveniles! Yes! Baby echinoderms! I've detailed this behavior in starfish in some detail here.   and of course, who can forget the life and death struggle of tiny asterinid starfish hermaphrodites who attack and eat one another in the "womb" of the mother?? (here)

Jannes' study focuses primarily on three brooding species in the South African area, including Amphiura capensis, Amphipholis squamata (both in the Amphiuridae) and one called Ophioderma wahlbergii

Jannes' work was actually surveyed here in GigaScience's own blog  Jannes and co authors use three dimensional visualization tools, including x-ray micro tomography scans to unobtrusively visualize brooding juveniles without destructively sampling the original specimen. Neato!

This gives you an idea of what Amphiura capensis looks like..
Image borrowed from Eastern Cape SCUBA diving! Go check em' out! 
Here's a visualization with CT Scan from Amphiura capensis!
which you can see more of here on this video

Jannes' study images brooding (i.e., the behavior of retaining the juveniles) in cavities called bursae which are located in the regions between the arms within the disk of the animal (in blue)
Here we have some just SPECTACULAR imagery of brooding in Ophioderma wahlbergii!
As it turns out, this will probably be a useful tool for non-destructively studying other brooding brittle stars and other echinoderms!

One South African brooding starfish (different from brittle stars) species which we know almost NOTHING about?? The South African "slime star" Pteraster capensis!  
Brooding cushion star, Pteraster capensis

and there are a MANY species of brooding brittle stars to choose from...

and this aptly named brooding species...Ophiacantha vivipara (from Rafael Martin-Ledo's neat but shortly lived Antarctic blog!)
Congrats to Jannes & my colleagues at Cape Town University for their new paper and looking forward to hearing more about their interesting future research!