Sea urchin mortality at the Johnson Atoll

Jamie D. Bechtel warrior at bu.edu
Fri Mar 8 16:36:32 EST 2002


Hello all -

I would like to add to Haris's suggestions.

I suggest that the entire echinoid complex should be surveyed when surveying
Echinothrix and Diadema during either preliminary studies or during or after
a die-off.

Having just completed five years of monitoring the recovery of echinoid
populations in Discovery Bay, it has become apparent that that the entire
echinoid complex may be playing an integral role in the recovery process.
Following a die-off of Diadema, we might see a loss of conspecifics as well.
It was hard to verify this in Jamaica as the historic data focused on D.
antillarum and T. ventricosus.  However, as D. antillarum recruited back to
Jamaica's north coast other species became more numerous as well.  We have
done some experimental work that further implies a relationship between
species. (manuscripts submitted).

With regards to Johnson Atoll, any estimates on percent loss of the two
species?

Cheers,
Jamie Bechtel

Jamie D. Bechtel, Ph.D., J.D.
Boston University
Department of Biology
5 Cummington Street
Boston, MA 02215
(617) 353-6969
warrior at bu.edu

___________________________

Original Message

Lindsey Hays, the refuge manager at the Johnson Atoll, reports widespread
mortality of Echinothrix (and maybe Diadema as well) all around the Atoll.
It seems that most of the sea urchins got sick and died rapidly.   He is
making efforts to collect samples, so that  the pathogens and the hosts can
be identified.

This may turn out to be a localized phenomenon, but this is what we
initially thought about the Diadema mortality in the Caribbean as well.
Just in case it spreads, it would be very useful for people in other areas
in the Pacific (particularly Hawaii and the Marshall Islands) to be ready
for it.  Surveys to determine population density of Echinothrix and Diadema
done now in unaffected areas can provide data that will become extremely
valuable.

It would also be a good idea to know ahead of time what to do if the
mortality should  appear elsewhere.  It is all common sense, but when things
are happening in a hurry, it is good to have a list.  If you notice sick or
dying sea urchins anywhere in the central Pacific:

1.Note  the date of the observation, and also note the date that populations
were last seen to be healthy.

2.  Collect specimens.  Some should be kept in 95% ethanol, some in 5%
formaldehyde, some frozen and (if possible) some should be cooled down on
ice for fast shipment to a microbiologist.

3.  If there are still healthy-looking animals around, collect some of these
too, so that their bacterial fauna can be compared with that of the sick
ones.

4.  If you have the time and the inclination, mark areas where the mortality
is occurring and areas where it does not seam to have reached yet.  Then
monitor these areas by counting numbers of healthy, sick and dead animals.

5.  Keep looking, even after the time that it seems that all the Echinothrix
is dead.  You may notice new ones emerging after a while (it happened with
Diadema antillarum).

6.  Don't expect the tests to stay around for very long.  They break down to
unrecognizable ossicles in a matter of days (parrot fish may help).

I hope that none of this will be necessary, because whatever is killing the
sea urchins at the Johnson Atoll will remain there.  Lindsay Hayes did a
great job of contacting people as soon as he realized that something was
amiss.  I wanted to spread the world around more widely in case things get
worse.

Haris Lessios

****************************
H.A. Lessios
Smithsonian Tropical Research Institute
Balboa, Panama

Telephone: +507/212-8708
Fax: +507/212-8790 or 212-8791
>From the US (domestic call): 202/786-2099 x 8708
Mail address:
>From the USA:
Unit 0948
APO AA 34002-0948
>From elsewhere:
Box 2072
Balboa, Panama

~~~~~~~
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digests, please visit http://www.coral.noaa.gov, click on Popular on the
menu bar, then click on Coral-List Listserver.

----- Original Message -----
From: Harilaos Lessios <LESSIOSH at naos.si.edu>
To: <coral-list at coral.aoml.noaa.gov>
Sent: Thursday, March 07, 2002 4:14 PM
Subject: Sea urchin mortality at the Johnson Atoll

> Lindsey Hays, the refuge manager at the Johnson Atoll, reports widespread
mortality of Echinothrix (and maybe Diadema as well) all around the Atoll.
It seems that most of the sea urchins got sick and died rapidly.   He is
making efforts to collect samples, so that  the pathogens and the hosts can
be identified.
>
> This may turn out to be a localized phenomenon, but this is what we
initially thought about the Diadema mortality in the Caribbean as well.
Just in case it spreads, it would be very useful for people in other areas
in the Pacific (particularly Hawaii and the Marshall Islands) to be ready
for it.  Surveys to determine population density of Echinothrix and Diadema
done now in unaffected areas can provide data that will become extremely
valuable.
>
> It would also be a good idea to know ahead of time what to do if the
mortality should  appear elsewhere.  It is all common sense, but when things
are happening in a hurry, it is good to have a list.  If you notice sick or
dying sea urchins anywhere in the central Pacific:
>
> 1.Note  the date of the observation, and also note the date that
populations were last seen to be healthy.
>
> 2.  Collect specimens.  Some should be kept in 95% ethanol, some in 5%
formaldehyde, some frozen and (if possible) some should be cooled down on
ice for fast shipment to a microbiologist.
>
> 3.  If there are still healthy-looking animals around, collect some of
these too, so that their bacterial fauna can be compared with that of the
sick ones.
>
> 4.  If you have the time and the inclination, mark areas where the
mortality is occurring and areas where it does not seam to have reached yet.
Then monitor these areas by counting numbers of healthy, sick and dead
animals.
>
> 5.  Keep looking, even after the time that it seems that all the
Echinothrix is dead.  You may notice new ones emerging after a while (it
happened with Diadema antillarum).
>
> 6.  Don't expect the tests to stay around for very long.  They break down
to  unrecognizable ossicles in a matter of days (parrot fish may help).
>
> I hope that none of this will be necessary, because whatever is killing
the sea urchins at the Johnson Atoll will remain there.  Lindsay Hayes did a
great job of contacting people as soon as he realized that something was
amiss.  I wanted to spread the world around more widely in case things get
worse.
>
> Haris Lessios
>
> ****************************
> H.A. Lessios
> Smithsonian Tropical Research Institute
> Balboa, Panama
>
> Telephone: +507/212-8708
> Fax: +507/212-8790 or 212-8791
> >From the US (domestic call): 202/786-2099 x 8708
> Mail address:
> >From the USA:
> Unit 0948
> APO AA 34002-0948
> >From elsewhere:
> Box 2072
> Balboa, Panama
>
>
> ~~~~~~~
> For directions on subscribing and unsubscribing to coral-list or the
> digests, please visit http://www.coral.noaa.gov, click on Popular on the
> menu bar, then click on Coral-List Listserver.
>
>

~~~~~~~
For directions on subscribing and unsubscribing to coral-list or the
digests, please visit http://www.coral.noaa.gov, click on Popular on the
menu bar, then click on Coral-List Listserver.



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