Effects of Invasive Plants on Wildlife

Mark HostetlerIFAS, University of Florida

Overview

• Wildlife – Basic Habitat Requirements– An example about birds

• Invasive Plants– How they disrupt wildlife habitat– Specific examples

• All animals need:–Food–Cover–Water–Space

Wildlife Habitat

Photo by Joe Schaefer

Habitat

Invasive Exotic Plant?

•An Exotic plant that is free-living and can cause

environmental or economic damage

•Considered invasive exotic by the Invasive Species

Working Group:

http://www.dep.state.fl.us/lands/invaspec/

Wildlife?

Shoal Bass

Alligator

Flatwoods Salamander

O.-crowned Warbler

Black BearKatydid

Habitat for Birds

FOOD

Insectivores

Photos courtesy of www.flwildflowers.com

Insect Eaters

Hairy Woodpecker

Yellow Warbler

Great-crested Flycatcher

Granivores

Sweet Gum Tree

Spanish Needle

Seed Eaters

White-crowned SparrowHouse Finch

Tufted TitmouseBlue Jay

Frugivores

Many different plant species produce fruit(e.g., hollies, cedar trees, beauty berries, wax myrtles)

www.flwildflowers.com

Beautyberry Holly spp.

Nectivores

Trumpet vine

Hummingbirds like to feed on plants that produce nectar

Coral Honeysuckle

Fruit and Nectar Eaters

Ruby-throated Hummingbird

Brown ThrasherCedar Waxwing

Northern Mockingbird

Carnivores

Meat Eaters

Barred Owl

Loggerhead Shrike

Great-horned Owl

COVER

Cavities

• Snags are in

short supply in

some habitat

Primary Cavity Nesters

Hairy WoodpeckerHairy Woodpecker

Pileated Woodpecker

Secondary Cavity Nesters

• Photos of owls, titmice, chickadees, etc.Tufted Titmouse

Great-crested Flycatcher

Carolina Chickadee

Eastern Bluebird

Vegetation for Cover

• Safety from predators

• Some nest on the ground where there is lots of vegetative cover

WATER

Aquatic Birds

Great Egret

Osprey

Space

Example: Trees and a Bird

How Do Invasive Plants Affect Wildlife?

• Food

• Cover

• Water

• Space

Effects of Invasive Plants on Wildlife Populations

• Create monocultures of new habitat

• Alter ecological processes (e.g., fire frequencies and intensity)

Air Potato(Dioscorea bulbifera)

• Covers mature trees and shades out understory vegetation

• Impact on wildlife has not been well studied

Australian Pine(Casuarina spp.)

• Quickly colonizes disturbed beach plant communities

• Invasions produce dense litter• Decrease in small mammal population

densities• Affects nesting efforts of sea turtles and

American crocodiles

Brazilian Pepper(Schinus terebinthifolius)

• Forms dense monospecific stands

• Fewer birds nest in pepper forests

• In some cases, fewer amphibians and reptile species were collected in pepper forests

Chinese Tallow(Sapium sebiferum)

• Forms dense monospecific stands• Increase nutrient loading on aquatic

systems• Impact on wildlife has not been well

studied

Hydrilla(Hydrilla verticillata)

• Reduces light penetration and low levels of dissolved oxygen beneath canopy

• Can shift macroinvertebrate populations

• In extreme situations, can affect growth rate of popular game fishes

• Food for some waterfowl species

Hydrilla

Old World Climbing Fern(Lygodium microphyllum)

• Dense blankets over native trees

• Insect diversity is decreased

• Impact on other wildlife has not been well studied

Melaleuca(Melaleuca quinquenervia)

• Extremely dense monospecific forests

• Some evidence that it causes wetlands to dry up

• Fires burn hotter in wetlands

Melaleuca

• Decrease in small mammal population densities (?)

• Poor forage for large vertebrates• Some birds are benefited• Generally, effects on wildlife not well studied

Torpedo Grass(Panicum repens)

• Forms extensive monospecific stands of grass

• Displaces native vegetation along shorelines

• Little value for fishes, waterfowl, or songbirds

Water Hyancith(Eichhornia crassipes)

• Forms dense aquatic plant canopy cover

• Low light intensities and dissolved oxygen levels

• Smothers beds of native submersed vegetation

• Can cause lower fish production

Spotted Knapweed(Centaurea maculosa)

• Reduced forage of elk between 50 & 90%

Leafy Spurge(Euphorbia esula)

• Reduced bison forage by 83%

Impact on Wildlife?

• Invasives change the environment (e.g., closed canopy and dissolved oxygen levels)

• Invasives replace native plants - most wildlife cannot eat invasive plants

• Disrupts food chain

• Web site: www.wec.ufl.edu/extension

• Call your local extension office

• Call Florida Fish and Wildlife Conservation Commission or visit www.state.fl.us/fwc

Where to Go for Info On Wildlife?

Where to Go For Info on Invasive Species?

•Center for Aquatic & Invasive Plants

http://plants.ifas.ufl.edu/

•Florida Exotic Pest Plant Council

http://www.fleppc.org/

•Department of Environmental Protection

http://www.dep.state.fl.us/lands/invaspec

What Can You Do?

•Remove Invasive Exotics on Your Property

•Report Invasive Exotic Plants

•Educate Your Neighbors About Invasive

Exotic Plants

Summary

• Wildlife Habitat:

- Food, Cover, Water, and Space

• Not well studied, but monospecific stands of

exotic plants do affect wildlife by replacing

native plant communities.

• Wildlife Info: www.wec.ufl.edu/extension

AcknowledgementsAcknowledgements

Developed byDeveloped by: :

Dr. Mark Hostetler, Department of WildlifeDr. Mark Hostetler, Department of WildlifeEcology and Conservation, IFAS, Ecology and Conservation, IFAS,

University of Florida, 2001.University of Florida, 2001.

AcknowledgementsAcknowledgements

Photo & Sound Credits:Photo & Sound Credits:

Mark Hostetler, Vic Ramey, Ann Murray, and Dan SudiaMark Hostetler, Vic Ramey, Ann Murray, and Dan Sudia

Invasive Plants: Center for Aquatic & Invasive PlantsInvasive Plants: Center for Aquatic & Invasive Plants

USGS Patuxent Bird Center (Bird Photos):USGS Patuxent Bird Center (Bird Photos):http://www.mbr-pwrc.usgs.gov/Infocenter/infocenter.html http://www.mbr-pwrc.usgs.gov/Infocenter/infocenter.html

FL Museum of Natural History: http://www.flmnh.ufl.eduFL Museum of Natural History: http://www.flmnh.ufl.edu