Loss of rare species can harm ecosystems

Mar 19, 2012 By Lori Lennon
Matthew Bracken, assistant professor of biology, surveys biodiversity along a rocky shore in Nahant. Credit: Michael Hutson.

(PhysOrg.com) -- Here’s another reason to cheer for the little guy. A new study co-authored by Matthew Bracken, assistant professor of biology in Northeastern’s College of Science, has found that rare species from the bottom of the food chain can have a large impact on an ecosystem’s health.

The findings were published in March in the online edition of the scientific journal Ecology Letters.

Bracken and Brown University student Natalie Low conducted several experiments that analyzed the impact of removing seaweed and sessile animals, such as mussels and barnacles, from the rocky shores of Northeastern’s Marine Science Center in Nahant, Mass. The experiments were designed to mimic naturally occurring changes in biodiversity on rocky shores.

The findings were startling. “We have shown that the loss of these extremely rare species — which collectively represent less than 10 percent of the seaweed and animal biomass at the base of the food web — causes major declines in the abundance and diversity of animals, such as snails, crabs and other mobile animals,” Bracken said.

Prior research on the extirpation of rare species from a particular ecosystem focused on how the loss of top predators — often referred to as “keystone” species — affects plants and animals at the bottom of the . Bracken and Low, on the other hand, have shown that the loss of from the base of the food chain, which they call “cornerstone” species, can also reshape marine systems.

A pattern of decline emerged after only three weeks of experiments and persisted for the remainder of the five–week study. “Previous work on the effects of rare predator removals took months to years to show strong effects,” Bracken said. “We found strong effects of rare seaweed removals after only a few weeks.”

Explore further: GMO mosquito plan sparks outcry in Florida

add to favorites email to friend print save as pdf

Related Stories

A call for an evolved understanding of emotion

Jan 04, 2012

(Medical Xpress) -- Many scientists believe that all people experience and express the same biologically “basic” emotions — an idea they have attributed to evolutionist Charles Darwin and one ...

The grass is always greener

Aug 19, 2011

(PhysOrg.com) -- Recent study of grasslands shows that species variety more important to ecosystem services than previously thought.

Researchers find a keystone nutrient recycler in streams

Jun 28, 2011

(PhysOrg.com) -- Researchers from the University of Georgia Odum School of Ecology have found that certain neotropical stream ecosystems rely almost entirely on a single fish species known as the banded tetra ...

Recommended for you

'Tiger heavyweight' Nepal hosts anti-poaching summit

38 minutes ago

Nepal's success in turning tiger-fearing villagers into their protectors has seen none of the endangered cats killed for almost three years, offering key lessons for an anti-poaching summit opening in Kathmandu ...

GMO mosquito plan sparks outcry in Florida

22 hours ago

A British company's plan to unleash hordes of genetically modified mosquitoes in Florida to reduce the threat of dengue fever and other diseases has sparked an outcry from fearful residents.

Population genomics unveil seahorse domain

Jan 30, 2015

In a finding vital to effective species management, a team including City College of New York biologists has determined that the lined seahorse (Hippocampus erectus) is more a permanent resident of the we ...

Researchers develop new potato cultivar

Jan 30, 2015

Dakota Ruby is the name of a new potato cultivar developed by the NDSU potato breeding project and released by the North Dakota Agricultural Experiment Station. Dakota Ruby has bright red skin, stores well and is intended ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.