What are polychaetes and why International Polychaete Day?

Polychaetes are segmented seaworms that are abundant in all marine and estuarine environments. This year, the first of July marks the first International Polychaete Day- a day of celebrating these amazing creatures. This day was selected as it would have been the 80th birthday of Dr Kristian Fauchald from the Smithsonian Institute of Natural History, who had spent much time at the Australian Museum working on our important polychaete collections.

Polychaetes occur at all depths from the intertidal zone to the deepest oceanic trenches. Over 20,000 described species have been classified into over 80 families. Polychaetes are a very old group with examples being found in the Cambrian, and they are most closely related to molluscs.

Polychaetes exhibit an amazing diversity of body forms, colour, and size and some are truly beautiful. Some are carnivores, other herbivores, filter feeders, some are parasitic and others swallow sediment to obtain their food. These animals can live from weeks to years, and show an amazing diversity of reproduction from mass spawning, others are brooders, some are hermaphrodites and many exhibit both sexual and asexual reproduction. If damaged they can regenerate their heads or tails.

The Australian Museum has a long history of seaworm scientific research and it hosts one of the largest polychaete collections in the world, representing over 1,500 species from 78 families. The collection includes ~45,000 specimen sample lots, ~600 microscope slide lots, ~800 SEM lots, ~600 frozen tissue lots and ~50 frozen genetic material preparations. Most of our worm collection is databased for easy access and the collection keeps growing as a result largely of our efforts and also through generous donations of our friends and colleagues around the world.

This 1st July 2015, worldwide, we are celebrating polychaetes for their amazing diversity, beauty and their important role in marine environments. This day would have been the 80th birthday of Dr Kristian Fauchald from the Smithsonian Institute of Natural History in Washington D.C. USA. Dr Fauchald worked on polychaetes for over 60 years and contributed immensely to our understanding of all aspects of their biology, ecology, reproduction and evolutionary history. Over decades, he spent several months here at the Australian Museum working on Australian polychaetes. He was here at the very first polychaete conference held in 1983 at the Museum and he most recently in 2013 when he participated in the 11th International Polychaete Conference also held at the Australian Museum.

Australia will be the first country to celebrate International Polychaete Day and as we move through the time zones, the celebrations will be continued in Europe (White Sea Biological Station of Moscow University, Russia, at National Museum of Wales, UK) and in the USA (Smithsonian Marine Station Aquarium in Fort Pierce, Florida and Smithsonian National Museum of Natural History in Washington, D.C. and then in Monterey Bay Aquarium Research Institute in California).

We hope this event will raise the awareness of the diversity and importance of polychaetes, a marine environment without such worms would be a very unhealthy place and our mud flats would be nasty smelly places. We need marine worms – just like you need earthworms in your garden and in the compost bin to break down organic matter and aerate the soils. They are at the bottom of the food chain and many animals rely on them for food.

Dr Pat Hutchings
Dr Elena Kupriyanova