A retrospective look at the early days
of HAB cyst research, and a look to
the future
On this occasion of the 25th anniversary of the publication of Harmful Algae News, several of us were asked to
look backwards in time to some of the
earlier days of HAB science. One area
of study that has been a major part of
my own research programme and that
of many others in our community is the
role of cysts and resting stages in the
bloom dynamics of HAB species. Here,
I offer a personal perspective on the
early stages of development in that field
and a brief look towards the future as
well. My apologies at the outset if there
are omissions of people or findings that
should have been included this is not
meant to be a scholarly synthesis, but
rather a personal retrospective.
To set the stage, lets go back nearly fifty years to a time when the term
harmful algal bloom did not exist and
when researchers worked individually or in very small teams in scattered
locations without any major research
programmes or international initiatives. In 1972 when I was just starting
graduate school, there was a massive
New England red tide caused by the
dinoflagellate we now call Alexandrium
catenella, but which then had multiple
names, including Gonyaulax tamarensis and G. excavata. This outbreak dealt
a devastating and unexpected blow to
the New England region of the United
States, causing shellfish closures along
the coasts of multiple states. Considerable attention by the press and public
covered this new and worrisome threat
to public health and fisheries resources
and ultimately motivated the First International Conference on Toxic Dinoflagellate Blooms in Boston, Massachusetts in
1974.
At the time of that conference, I was
a long-haired graduate student in the
Civil and Environmental Engineering
Department at MIT (Fig. 1), searching
for a thesis topic. People often ask me
how someone in an engineering department could end up a biologist working
on HABs, and the answer to that lies in
part with the 1972 New England red
tide, but also with the 1974 conference
and a series of events and discoveries
4
former used to disaggregate sediments
and the latter to separate size fractions
containing cysts. In his paper in the
1974 conference proceedings and in
other papers published near that time
[1-3], Wall highlighted the important
roles that cysts likely played in dinoflagellate bloom dynamics, including determining where and when blooms might
originate, allowing survival through environmental extremes, and facilitating
genetic recombination through sexuality. He told us Despite these seemingly
important considerations, the encystment-excystment cycle in dinoflagellates
has not been expressly studied in relation to any specific red tides or related
instances of paralytic shellfish poisoning. Details of the cyst cycle have been
accumulated independently of red tide
research..... [1]. This contribution and
other papers at the time show considerable foresight that was fully validated
through a sharp increase in the cystbased HAB research of the subsequent
decades.
Another talk at that conference was
equally insightful, this one by Karen
Steidinger (Fig. 3) (Basic factors influencing red tides [4]). In her talk and
paper, Karen outlined the fundamental
stages of blooms, focusing on initiation,
transport, and development. Like Dave
Wall, she also highlighted the importance of cysts: The recent investigations
of Dr. David Wall ......lend credence to
the speculation that pelagic, toxic dinoflagellate blooms might originate from
that came shortly before and after.
The conference was very small compared to the current ISSHA meetings,
with approximately 100 participants
from four countries versus 500 or more
participants representing 50 or 60
countries at our current meetings. The
focus of that meeting was almost entirely on blooms of Alexandrium catenella
and Karenia brevis (the species was then
called Gymnodinium breve), as the discoveries of diarrhetic shellfish poisoning (and its linkage to Dinophysis spp.)
and amnesic shellfish poisoning (and
Pseudo-nitzschia) were 10-15 years in
the future. The ciguatera fish poisoning
syndrome was known, but the identification of Gambierdiscus toxicus as the
causative organism was also several
years away. Among the contributions at
that meeting, several are noteworthy in
the context of the theme of this narrative. The first was by David Wall, a geologist at the Woods Hole Oceanographic
Institution (Fig. 2). In the late 1960s
and early 70s, Wall (working with Barrie Dale at the time) discovered that
the fossilized cell walls of organisms
thought to be extinct (called hystrichospheres) were in fact dinoflagellate
cysts, and that many of the forms that
they were using in paleontological reconstructions were
still living in the
ocean and producing cysts that could
be germinated to
establish taxonomic affinities. (This
same line of work
was concurrently
being pursued by
Bill Evitt and colleagues at Stanford
University). In order to isolate and
germinate
living
cysts from modern
sediments,
Wall
and Dale developed
a technique that is
used to this day in- Fig. 1. Don Anderson as a graduate student in the Civil and Environvolving sonication mental Engineering Department at the Massachusetts Institute of
and sieving the Technology (MIT), 1975
HARMFUL ALGAE NEWS NO. 59 / 2018
Harmful Algae News An IOC Newsletter on Toxic Algae and Algal Blooms No. 59 - February 2018 www.ioc-unesco.org/hab Content 25 years of HAN and IPHAB...... 1 25 YEARS Harmful Algae News was first published in early 1992 in response to requests from the participants at a number of IOC meetings and
pacted by harmful algal events. Since Harmful Algae News turned 20 years old in 2012, it has been a web based e-newsletter which meant longer issues were possible and back issues easily accessible. We are currently working on a searchable index for all Harmful Algae News issues. The start of Harmful
Intergovernmental Panel on Harmful Algal Blooms also turned 25! During 1992, the same Year as the IOC published the first issue of Harmful Algal News, it also established an Intergovernmental Panel on Harmful Algal Blooms (IPHAB) which has met every second year since it was formed. The Panel is com
A retrospective look at the early days of HAB cyst research, and a look to the future On this occasion of the 25th anniversary of the publication of Harmful Algae News, several of us were asked to look backwards in time to some of the earlier days of HAB science. One area of study that has been a ma
dormant stages and that these stages might be associated with certain bottom sediments. This then brings up the question, if benthic resting stages of certain dinoflagellates actually seed coastal red tides, are there localized areas of accumulation, or what we could call seedbeds?..........The poss
day, we still do not know if there are other factors at work perhaps a density-dependent or quorum-sensing type of response, or even a response to the presence of grazers or parasites. Exploration of this response has long been limited by the constraints associated with laboratory cultures, but now
approach did not stand up to data at my study locations. I raise this issue in this narrative because I want to correct what I feel are unjustified recommendations that may prevent those working on cysts from obtaining the type of biological data that can advance our understanding of certain types o
number of cysts in subsurface layers unable to germinate or emerge, presumably due to lack of oxygen or to the tortuous pathway posed by sediment grains and detritus. Many might think that major storms and waves can erode significant layers of sediment and transport cysts long distances, but here ag
How do algal blooms kill finfish and how can we mitigate their impacts? Algal blooms, water discolorations and their association with fish kills have been recorded since historic times, such as the description in the Bible (1000 years BC) all the waters that were in the river were turned to blood. A
Table. 1. Economic losses from algal blooms for finfish aquaculture in different parts of the world HAB species Chattonella Heterosigma Cochlodinium polykrikoides Heterosigma Chaetoceros Heterosigma Karenia digitata Karenia mikimotoi Country Financial Losses Japan Korea, China Canada British Col
emergency harvest operations. To prevent the buildup of histamines, fish should be kept alive as long as possible during harvesting. This can be achieved by diluting algal concentrations via airlift upwelling, or by targeted in-pen emergency application of clays [23] that mop up ichthyotoxins at cla
As part of the 25th anniversary issue of Harmful Algal News I am providing an overview of the IOC-UNESCO Taxonomic Reference List of Harmful Algae (www. marinespecies.org/hab/) and will highlight some of the problems which have faced or are facing the Intergovernmental Panel on Harmful Algal Blooms
Dinophyceae the authors intended the new genus to be described according to the botanical nomenclature. The lack of a Latin diagnosis therefore made it invalid. The confusion has actually still not been resolved, and the problem needs to be discussed and decided upon by the International Nomenclatur
geographically widespread species being able to form fertile offspring, while other populations of the same species are not. Molecular techniques have contributed very significantly to solving many taxonomic problems, but they have not resulted in the emergence of a finite species concept. We have t
Algal toxin discovery, management and regulation over the last 25 years Algal toxins in the dark ages (pre-1992) From a historic perspective, knowledge about algal toxins can be divided into truly prehistoric occurrences such as known from paleontological studies [1-2] and more recent historic recor
lar rapid increase in known analogues has been observed for the azaspiracid (AZA) group, with the first analogue described in 1998 [64] and a review in 2014 reporting 30 analogues [65]. Only three years later, over 50 analogues are known for this group, including novel phosphate derivatives [66-71].
Butterflies in Brazil Abstracts are not always reliable guides to authors intentions. They are not expected to reveal a great deal about the evidence to be deployed in support of the science, evidence that may not even exist before deadlines for writing abstracts! Nevertheless, as examples of a mino
on a decadal time scale, and identified palaeoclimatic oscillations are not necessarily a useful guide to its interpretation. An obvious obstacle to detecting climate signals in HAB data is posed by anthropogenic eutrophication. Another obstacle is the fact that phytoplankton respond directly to the
trends, Karenia brevis might appear more often in the South Atlantic Bight of the US and Gymnodinium catenatum bloom more often in northwestern Iberian waters. There was also a warning by Barrie Dale germane to such speculations, that large scale climate models cannot predict local changes. Little m
Red tides in Kamchatka coastal waters (Bering Sea, Russia) are a barrier for the salmon fishery and Pacific salmon Fig. 1. Map of Olyutorskiy Bay (Kamchatka, Bering Sea) where a red tide, reported by fishermen, occurred in July 2017. The stars denote fishery sites: red, affected by the bloom; green
Fig. 2. Red tide in Olyutorskiy Bay on 15th July 2017 grounds of the Olyutorskiy Bay river basin performed during the second half of August showed an atypical distribution in the rivers. Maximal escapes were recorded in river basins located in the western and eastern parts of the Olyutorskiy Bay ar
First report of Gambierdiscus in the Western Mediterranean Sea (Balearic Islands) Gambierdiscus (Dinophyceae) species are benthic dinoflagellates living in marine littoral zones of circumtropical areas and have recently been described in temperate waters [1]. Some species are producers of potent neu
the SEASENSING (BIO2014-56024C2-2-R) project and the CERCA Programme/Generalitat de Catalunya. A. Tudó and A. Toldrà acknowledge IRTAURV-Banco Santander for their respective PhD grants (2016 PMF-PIPF-74 and 2015PMF-PIPF-67). The authors are grateful to Vanessa Castan and José Luis Costa for sampling
Comparison by light microscopy and qPCR of potentially ichthyotoxic microalgae in Danish on-shore lagoons producing European flounder (Platichthys flesus): Pros and cons of microscopical and molecular methods Fig. 1. Lagoon used for production of European flounder at Fishlab, Denmark. Evaluation o
Fig. 2. Comparison of phytoplankton species identification and cell densities (cells L-1) by qPCR (A and C) and light microscopy (target species and groups which potentially could comprise ichthyotoxic organisms) (B and D) in lagoon 1 (A and B) and lagoon 6 (C and D), respectively. The right Y-axis
present in a sample then qPCR would miss those probably due to lack of a developed assay. However, LM does require high levels of taxonomic skills and the precision in identification is only as accurate as the taxonomist allows. Different taxonomists trained in different ways using different identif
As qPCR measures genetic material rather than viable cells an over estimation of cell numbers can occur due to the inclusion of dead or dying cells. Problems may also occur when targeting multiple copy genes where the organism carries different numbers of the target depending on nutritional status,
The Cawthron Institute Culture Collection of Micro-algae (CICCM) The CICCM is designated as a nationally significant database by the New Zealand government and so receives partial funding for its continued existence. Isolates from 13 classes of micro-algae are maintained either as live cultures or c
The XVIII International Conference on Harmful Algae is approaching! It is time for nominations for achievement awards (Yasumoto Life Time and Patrick Gentien Young Scientist), registration to the conference as a student if you wish to participate in the Maureen Keller Award competition and fundraisi
Forthcoming Events First announcement of the 11th International Conference on Toxic Cyanobacteria (ICTC) We are pleased to disseminate the first announcement of the 11th International Conference on Toxic Cyanobacteria (ICTC) that will be held in Krakow, Poland from May 5 10, 2019. The ICTC is a per
International Coordination of Research on Harmful Algal Blooms From GEOHAB to GlobalHAB International cooperation is fundamental to advance understanding of HAB dynamics and to improve our ability to predict them. Fostering this international cooperation was the mission of GEOHAB (Global Ecology and
18th International Conference on Harmful Algae www.icha2018.com IMPORTANT DEADLINES Abstract submission deadline: 15 April 2018 Early bird registration: 15 July 2018 Get the 17 ICHA Proceedings at www.issha.org Eds-in-chief Beatriz Reguera, IEO, Vigo, Spain Eilen Bresnan, MARLAB, Scotland, UK Regi