WHAT ARE HAB's ?

Harmful algal blooms (HABs) are proliferations of algae that can cause massive fish kills, contamination of seafood with toxins, and/or ecological damage through the development of anoxia or habitat alteration.

Such blooms cause world-wide problems with significant economic, social, and human health consequences. There is now considerable evidence that certain HABs, or at least their associated impacts, may be increasing globally. As with all phytoplankton dynamics, those of harmful algal species result from a combination of physical, chemical, and biological processes, many of which remain poorly understood. 

Some HABs have been linked to changes in nutrient inputs to coastal ecosystems, particularly as a consequence of human activities, but many harmful events occur in areas where anthropogenic input of nutrients or other pollutants are not considered to be contributing factors. The effects of global or local climate change on HAB populations are even less well understood.

In spite of considerable research on HABs over the past few decades, particularly on their distribution, environmental impacts, and effects on human health, the ability to describe factors controlling the dynamics of individual species, or species groups, has been limited by critical gaps in knowledge of the physiological, behavioural, and genetic characteristics of these taxa. In particular, there is an incomplete understanding of the interactions between physical and other environmental conditions that promote the selection of one group of species over another. Most previous research on HABs has been supported at the local or national level, with few attempts to consider such events from the ecosystem perspective at the appropriate regional scale. Furthermore, there has never been a programme designed to study such phenomena with a view to integrating global data from comparable ecosystems. GEOHAB is an international, multidisciplinary, comparative approach which will advance our understanding of the mechanisms underlying population dynamics of HABs in differing physical and oceanographic regimes.