2019 IRPS Distinguished Lecturer

Life, turmoil, and abundance in Monterey Bay: how we study it and what sponges have to do with it

Dr. Amanda S. Kahn, Monterey Bay Aquarium Research Institute

1:20 PM, Wednesday April 3, Regency Main


Monterey Bay is a dynamic region known for its natural features, tide pools, beaches, and the abundant marine life it supports. This talk will begin by introducing the violent forces – earthquakes, landslides, volcanoes, and pounding surf – that have shaped the California coastline (and specifically Monterey Bay). It will then focus on how diverse ecosystems – on land and in the ocean – are supported by the turbulent ocean.  The second half of the talk will focus on how animals make a living in one of the most extreme environments on the planet: the deep ocean.  The deep seafloor makes up 80% of the planet’s surface and is readily accessible in Monterey Bay due to the Monterey Submarine Canyon, although accessing it requires advanced technology and approaches.  MBARI specializes in developing technology to study the deep ocean such as hydraulically powered remotely operated vehicles powered by kilometers-long fiber optic cables, autonomous underwater vehicles capable of surveying the seafloor for weeks on end, and sensors designed to withstand near freezing temperatures and the weight of over a thousand meters of water compressing them.

Seafloor communities in these deep habitats cannot rely on locally produced food as light cannot penetrate to fuel photosynthesis. Deep-sea communities thus rely mainly on imported nutrients, either as material sinking from the surface or arriving via lateral currents.  The food that arrives is often limiting, yet in some locations, dense communities manage to persist and even flourish.  Suspension feeders – animals that capture food particles suspended in the water column—are important vectors for transferring food energy from the water column into the benthic food web.  Dr. Kahn’s research focuses on one group of suspension feeders that is highly successful at surviving in the deep sea: the sponges (Phylum Porifera).  Through their feeding activity, sponges act as oases of nutrients in the food-poor deep ocean.


Dr. Kahn’s research broadly focuses on the movement of food energy (carbon) within and between ecosystems, and on how animals facilitate this movement – especially in the food-starved deep sea.  Her research has involved studies of deep-sea sponges from extinct underwater volcanoes off the coast of California, the unique glass sponge reefs of western Canada, and ‘cheese-bottom’ sponge grounds in the fjords of Norway.  Dr. Kahn received her PhD in Ecology from the University of Alberta in Edmonton, Alberta, Canada.  She completed postdoctoral fellowships studying sponges in the deep north Pacific and oceanography of the North Atlantic, and is now currently a postdoctoral fellow in the benthic ecology lab at the Monterey Bay Aquarium Research Institute.  She is preparing to transition to Moss Landing Marine Laboratories to begin as an assistant professor in invertebrate ecology in August this year.