Apex Predator Removal

Ian CraickBernice Longouo

Jeremy Raynor

A Case Study on the removal of

sharks and wolves

Apex Predators?

Apex predators are the top level predators in an ecosystem. This means that they have no natural predators

Humans become predators – upset the natural balance

Removal? What is removal? How are predators removed?

Why do we care?

Ecosystems Services Ecosystem dynamics and function Energy and nutrient flow Human Health

PART I – The Critical Issue

The importance of predation- predators have a fundamental influence on structure and function of ecosystem- Predators influence prey population and communityPredation affect prey behavior. Presence of predator allow prey to use behavioral mechanism to reduce predation risk.

Facts and figures of decline

Large shark populations down by about 90% or more regionally

Found out of 547 species studies 20% were threatened (sharks, rays, chimaeras)

Difficult to measure due to mobility and low populations of target species Nicholas Dulvy 2006

Heithaus et al. 2008

PART II - Effects on Nutrient Cycling

How do apex predators influence Nutrients flow? Mainly through Biologic factors Two methods:

-Top Down Control-Trophic Cascades

Top down Control

Changes in top predators influence the abundance and behavior of organisms in lower trophic levels

Trophic Cascade

Top predators influence trophic levels two or more levels below them

Post 1999

Wolves

Wolf removal has seen major spikes in Deer, Elk, Moose and other prey populations

Wolf re-introduction has seen decreases in prey populations and significant increases in foliage

Yellowstone

Last Wolves exterminated in 1926 within the park Re-introduced in 1994-95 Pack reached a record high of approximately 40

individuals Elk populations rise when wolves are

exterminated, decreased after peak (resource limited) then decreased to ~pre-extermination levels after re-introduction of wolves

Sharks

Shark presence shapes prey behavior Shark Bay, Australia Behavior changes

-Spatial-Temporal

PART III – The Causes

Fear – Politics – Apathy – Ignorance - Greed

Major Declines – USA & Globally

North American Gray wolf (canus lupus)

Black Tip Shark population off the East Coast of the United States

Heithaus et al. 2008 article FIU

Ripple et al 2005

Shark Finning

Shark Finning

Fear – Ideas of sharks as competitors and dangerousMoney – Shark fin soup market growth in ChinaAccidental Catch (bycatch) Long Lines, Trolling, Siene Netting

Shark Finning

Systematic, Organized Killers (us)

Wolf “Culling” (that means killing)

Defenders of Wildlife Wolf Video Clip

State-funded culling programs

Last month, Idaho’s Governor Otter signed a bill creating a $400,000-per-year wolf extermination fund. 

Approximately 1,300 Wolves have been killed in Idaho alone since 2011

PART IV – Conclusions & Solutions

There ARE solutions There ARE things YOU can do to help

Scientifically proven equations for success

Protection = Preservation + Conservation

MPA (Marine Protected Areas) National Parks IUCN Red List (International Union for Conservation of Nature) CITES (International Trade Regulations) Magnuson-Stevens Act (Fishery Conservation, Mgmt.

USA) Shark Finning Prohibition Act (USA) ESA - Endangered Species Act (USA) Biodiversity Hot Spots

Awareness = Advocacy + Education

Education based on Long Term Scientific Studies

Advocacy based on the facts, environmental lobbyists

Awareness & Action:1. Know the issue from multiple perspectives

(Volunteer)2. Know the history and current situation

(Investigate)3. Make a difference voice your opinion & support

research

References

Abesamis, R A, and G R. Russ. "Density-dependent Spillover from a Marine Reserve: Long-Term Evidence." Ecological Applications. 15.5 (2005): 1798-1812. Print.

Beschta, R L, and W J. Ripple. "River Channel Dynamics Following Extirpation of Wolves in Northwestern Yellowstone National Park, Usa." Earth Surface Processes and Landforms : the Journal of the British Geomorphological Research Group. 31.12 (2006): 1525-1539. Print.

Dulvy, Nicholas K. "Conservation Biology: Strict Marine Protected Areas Prevent Reef Shark Declines." Current Biology. 16.23 (2006). Print.

Graham, Nicholas A. J, Mark D. Spalding, and Charles R. C. Sheppard. "Reef Shark Declines in Remote Atolls Highlight the Need for Multi-Faceted Conservation Action."Aquatic Conservation: Marine and Freshwater Ecosystems. 20.5 (2010): 543-548. Print.

References

Heithaus, MR, A Frid, AJ Wirsing, and B Worm. "Predicting Ecological Consequences of Marine Top Predator Declines." Trends in

Ecology & Evolution. 23.4 (2008): 202-10. Print. Kareiva, Peter. “Conservation Biology: Beyond Marine Protected

Areas” Current Biology. 16.14 (2006). Print. Knip, D.M, M.R Heupel, and C.A Simpfendorfer. "Evaluating Marine

Protected Areas for the Conservation of Tropical Coastal Sharks." Biological Conservation. 148.1 (2012): 200-209. Print.

Ripple, William J., and Robert L. Beschta. "Linking wolves and plants: Aldo Leopold on trophic cascades." BioScience 55.7 (2005): 613-621.

Robbins, William D, Mizue Hisano, Sean R. Connolly, and J H. Choat. "Ongoing Collapse of Coral-Reef Shark Populations." Current Biology. 16.23 (2006): 2314-2319. Print.

Post, Eric, et al. "Ecosystem consequences of wolf behavioral response to climate." Nature 401.6756 (1999): 905-907.

Apex Predator Removal

Ian CraickBernice Longouo

Jeremy Raynor

A Case Study on the removal of

sharks and wolves

“To keep every cog and wheel is the first precaution in intelligent tinkering” –Aldo Leopold