trophic cascades

As an ecologist I have spent the past ten years of my professional career tracking apex predators and large herbivores and their effects on whole ecosystems. Abundant research from all sorts of systems demonstrates that when you allow dominant species, such as lions or elephants, to return to ecosystems, they affect many other species in those systems. For example, by toppling small trees, elephants help maintain the rich, open grassland habitat that provides a home for countless species, such as songbirds and insects.

This excellent post at The Fisheries Blog  uses a vist to the Monterey Bay Aquarium's kelp forest to explain the concept of trophic downgrading. The post references the seminal Science report on the topic co-authored by James A.

We have been discussing the powerful and essential ecological link between apex predators, their prey, and the foods prey eat. Based on the revolutionary ideas of Hairston, Smith, and Slobodkin, who in 1960 ingeniously proposed that the world is green because predators limit their plant-eating prey, trophic cascades science has since then explored the consequences of predator removal from ecosystems worldwide.

Washington State’s old-growth rainforests are among the richest communities on earth. These ancient forests support astonishing biodiversity due to their high moisture, nutritious soil, and architecture. The Douglas-fir, a formidable tree giant that can live over 1,000 years, embodies these forests’ physical characteristics. Its 500-foot-tall, multilayered canopy, thick trunk, and enormous volume (called “biomass”), whether living or dead, provides home for many species.