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Vertebrate Pest Management

Chapter 18

Vertebrates

• Animals with an internal skeleton made of bone are called vertebrates.

• Vertebrates include:– Mammals

• Raccoons, opossums, deer, rodents

– amphibians;

– reptiles;

– birds; and,

– fish.

Before Starting with a Management Program

• Determine what kind of animal is doing the damage.– Identification is essential for effective management.

– Signs may offer clues to identification.

• Determine cost of control verses damage.

• Determine aesthetic, recreational and legal status of species involved.

• Determine effect of control on nontarget animals and the environment.

Population dynamics and pest management

• Population dynamics:– How populations change in relation to the

environment.

– By manipulating habitat some pest can be managed without resorting to chemicals or traps.

– Each area has a limited carrying capacity

Carrying Capacity:

• Is determined by by three limiting factors:– Food

– Water

– Shelter

• Control of these factors can manipulate the population density.

Managing vertebrate pests• Steps to effective rat and

mice control:– Eliminate harborage(shelter)

– Rodent-proofing structures

– Eliminate food and water

– Killing the rodents• Rodenticides

– Anticoagulant

» Warfarin

» d-CON

– Nonanticoagulant

» Cholecalciferol

» Bromethalin

» Zinc phosphide

• Trapping

• Electronic sonic repellers

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Anticoagulant:• Warfarin and d-CON is used for controlling

rats and house mice in and around homes, animal and agricultural premises, and commercial and industrial sites.

• It is odorless and tasteless and effective in very low dosages.– Action is not rapid; usually about a week is

required before a marked reduction in the rodent population is noticeable.

– Rodents do not tend to become bait-shy after once tasting warfarin; they continue to consume it until its anti-clotting properties have produced death through internal hemorrhaging.

– Repeated ingestion is needed to produce toxic symptoms.

Anticoagulant: Coumarin• Coumarin is found in many

plants, including lavender, woodruff, and sweet clover; and also in strawberries, apricots, cherries, and cinnamon. Coumarin smells like vanilla but what little flavor it has is bitter. This may serve to repel some insects. It is found in high percentages in the tonka bean (Dipteryx odorata, Fabaceae (Pea) Family). Tonka bean extract is commonly used to adulterate vanilla in Mexico.

Cholecalciferol• Cholecalciferol-containing rodenticides are

used to control mice and rats.– Rodents generally die within 2 days following

ingestion and do not appear to exhibit bait shyness.

– Cholecalciferol-containing rodenticides increase absorption and serum concentrations of calcium and phosphorus.

• Trade names of the cholecalciferol-containing rodenticides include: – Quintox® – Ramapage® – Ortho Mouse-B-Gone® – Rat-B-Gone®

Bromethalin

• is a highly potent rodenticide that provides a lethal dose to rodents in a single feeding.– Death occurs within 24 to 36 hours after ingestion.– It is a pale, odorless, crystalline solid compound in

the diphenylamine family. Its mechanism of action is to uncouple oxidativephosphorylation in the mitochondria of the central nervous system--causing damage to nerve axons, inhibiting neural transmission and leading to paralysis, convulsions and death.

Zinc phosphide• Zinc Phosphide is an inorganic

chemical that is used to control rats, mice, voles, ground squirrels, prairie dogs, nutria, muskrats, feral rabbits and gophers.– It may be formulated as a grain

based bait, as scrap bait or as a paste.

– Rodenticide baits usually contain 2.0 percent of zinc phosphide.

– Zinc phosphide reacts with water and acid in the stomach and causes severe irritation

Bats• Pro:

– Eat insects.– Do no damage to

structure.

• Con:– May be noisy– Carry parasites– Produce guano– May transmit rabies

• Control:– Exclusion

Cimex lectularius(The Bed Bug)

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Mole or Gopher?Diet Mole or Gopher?

Digging Habits

Mole or Gopher?Appearance

Mole or Gopher?Digging Habits

Moles

Shrew-mole (Neurotrichus gibbst)

Coast mole (Scapanus orarius)

Broadhanded mole

Townsend mole Moles• Contrary to popular belief, moles do not eat

the roots and bulbs of flowers and vegetables.

• In fact, they may benefit these plants by feeding on grubs and worms that can damage them.

• However, the tunneling activities of moles may disfigure lawns and gardens.

• Since mole damage is usually isolated and of little economic consequence, localized control techniques are more practical than a wholesale eradication program.

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Moles

• Moles have enormous appetites and may eat up to 100 percent of their body weight in a single day.

• Moles feed primarily on insects that feed below the ground.

• Moles eat mostly white grubs, earthworms, beetles, and assorted larvae.

Moles

• Moles are usually solitary, although females and young may share the same burrow.

• The tunnels that the mole makes while searching for food may be used only once or may be traveled repeatedly.

• Moles may be active during any time of the day and seem to prefer cool, moist soil (the same as that preferred by grubs and earthworms).

Controlling Moles• Trapping• Soil Insecticides• Mole baits• Castor-oil• Fumigants and gas

bombs• Mole plants,

chewing gum, and mothballs.

Controlling Moles• Trapping• Soil Insecticides• Mole baits• Castor-oil• Fumigants and gas

bombs• Mole plants,

chewing gum, and mothballs.

Lethal Mole Control

• Lethal traps are usually of three types:– harpoon,

– scissor-jawed,

– and choker.

Controlling Moles

• Trapping

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Biological Mole Control

• Biological, nonlethal mole control may be achieved by eliminating the food source.

• This can be accomplished by using insecticides for controlling grubs.

• White grubs may be controlled naturally by introducing milky-spore disease into the soil.

• While these techniques may be effective, they are not quick. It may take some time before the food supply is reduced enough to affect the mole population.

Pocket gophers (Thomomys spp.)• Traps

– Most successful when mounds are formed

– Locate main runway– Place two traps in

runway

Pocket gophers (Thomomys spp.)• Follow Calendar

– For most successful control techniques

Pocket gophers (Thomomys spp.)• Traps

– Most successful when mounds are formed

– Locate main runway– Place two traps in

runway

Pocket gophers (Thomomys spp.) Pocket gophers (Thomomys spp.)

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Pocket gophers (Thomomys spp.)• Baits

– Locate tunnels

– Bait in two or three places

Pocket gophers (Thomomys spp.)

• Fumigants

Voles (Microtus spp.)• All are plant feeders

• Proficient burrowers

• Damage orchards by feeding on trunk and roots.

• Tunnel through vegetable and flower gardens

• May use mole tunnels.

Voles (Microtus spp.)• Management

– In orchard: control vegetation around trees.

– Mow grass between trees.

– Avoid loose mulch around trees.

– In Gardens: keep area around gardens free of tall grass.

– Fallen seeds from bird feeder attracts rodents

Voles (Microtus spp.)• Biological

• Mechanical

• Chemical

Ground Squirrels

• Management and Controls– Exclusion of

buildings– Use metal guards

around fruit and nut trees.

– Trapping effective with small numbers

– Rodenticides are effective if legal

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Ground SquirrelsTree Squirrels

• Squirrels become a problem when they attack fruit, nut and vegetable crops.

• Control:– Use metal tree

guards

The Truth About SquirrelsMountain beaver (Aplodontia

rufa)• Become pest when

they feed in reforestation units, Christmas tree farms, yards, and gardens.

• Control: Use cage trap

Deer and Elk• Three species of deer:

– Whitetail

– Blacktail

– Mule deer Mule deer

Blacktail

Whitetail

Deer and Elk• Two species of

elk:– Rocky Mountain– Roosevelt

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Elk in the Rogue ValleyDeer Damage-Browse

Deer Damage -Rub Twig Dammage

Deer Management

• Deer resistant plants• Repellents• Scare devices

– Mechanical– Dogs

• Exclusion– Fences– Netting

Deer and Elk

• Effective commercial repellents include Deer-Off and Deer-Away.

• One of the most effective homemade repellents can be made by whipping one part whole eggs with four parts of water. – Apply on a dry day with temperatures above freezing.– This egg spray does not readily wash away and is not harmful to

plants.

• Apply or hang repellents within the new growth. Young trees should be treated completely, but older trees may be treated only on the branch tips.

• Re-apply the repellent every 30 days.• No repellent will be active forever and deer may get used to egg

sprays. When this happens, try other measures and be persistent.

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Motion DetectorsMotion detectors will set off sprinklers to frighten deer or other animals. They often get accustomed to this type of device.

The critter gitter sets off a variety of high frequency sounds and blinking red lights.

Deer and ElkHerding breeds of dogs

– Abruzzese – Bearded Collie– Collie (rough)– Belgian Tervuren– Bouvier des Flanders– Briard– Belgian Sheepdog– German Shepherds– Old English Sheepdog– Cardigan Welsh Corgie

Deer and Elk

• Electronic pet barriers are useful at excluding deer in areas where damage occurs. Dogs fitted with electronic collars enclosed in an area by a wire that activates the collars have reduced deer damage dramatically.

Deer and Elk

When using an electronicpet barrier, the following points are vital.

– 1) The wire that activates the shock collars does not have to be buried.

– 2) Herding breeds of dogs (e.g. border collies) have been more reliable than confirmed deer-chasing mongrels.

– 3) The dogs must be trained to the wire initially. Visual indicators of the position of the wire help train the dog.

– 4) Male dogs (2 or more) are better than female dogs.– 5) The dogs must be housed and fed within the wire.– 6) The number of dogs needed per unit of area is

unknown. Two dogs may protect 15 acre research plots. Long term effectiveness is unknown.

Deer and Elk

• Fences protecting individual plants or small groups of plants should be at least four feet high. These enclosures are effective because deer avoid tight, penned-in sites. Garden netting may protect flowerbeds and other low-growing plants.

4ft High ?

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Deer Cages Netting

Deer and ElkUsed for deer, elk,

bison, ostrich, wildlife control, and security fencing.

Wire mesh fences are more effective than wood fences, although not generally 100 percent effective.

Deer and Elk

Vertical wire garden fences should be at least eight feet high.

Deer and Elk

Slanted fences should lean away from the Garden at a 30 to 45 degree angle from the ground and should be at least six feet high. This creates both a physical and psychological barrier to deer. Electric fences also can be used.

Deer and Elk

• Tubes placed around the trunks of larger trees will help prevent trunk damage.

• Tubes will not prevent trunk damage when bucks use the trees to scrape the velvet off their antlers.

• Fencing trees may help keep deer away.

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Wireless Deer FenceThese fence posts attract deer to them with a pleasant scent then shock them when they touch the top ball.

These posts have been tested for five years and have proven very effective at keeping deer out of yards

Placing three or four around your yard near favorite plants or gardens works well

Rabbits• Rabbits eat a variety of

herbaceous and woody plants.

• Exclusion with 2 ft high chicken wire fence is usually effective.

Raccoons and

Skunks• They are vectors of

rabies.

• They raid gardens and orchards.

• Control:– Metal guards

– Radio

– Dog

Opossums

• Opossums are omnivorous feeders.

• May nest under houses.

• Control:– Metal guards

– Radio

– Dog

Birds• Birds cause

problems by their:– Roosting

– Nesting• Droppings

• Disease

– Feeding habits• Cherries

• Blueberries

• Grapes

• Strawberries

Birds

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Birds

• There are two main diseases that can breed within pigeon droppings. These diseases are actually funguses known as Histoplasmosisand Cryptococcus.– When pigeon droppings are disturbed, small

particles become airborne which may contain these funguses.

• Histoplasmosis primarily affects a persons lungs, and symptoms may vary greatly. If symptoms do occur, it is usually between 3 to 17 days after exposure and will appear as a flu-like respiratory illness.

• Cryptococcus is an encapsulated fungus that also enters the body through the respiratory system. Once in the lungs for a period of time, the organism will then spread through the blood stream.

Diseases Associated with Pest Birds

• Bacterial –– Paratyphoid, Vibriosis, Salmonella, Listeriosis

& Pasteurellosis

• Viral –– Encephalitis, Meningitis, Newcastle Disease &

St. Louis Encephalitis

• Fungal –– Histoplasmosis, Candidiasis,

Sarcosporidiosias & Blastomycosis

• Protozoal –– Toxoplasmosis, Trichomoniasis & American

Trypansomiasis

Corrosion of Surfaces• Bird droppings are very acidic and

can eat away at construction materials.– An accumulation of droppings can

shorten the life span of a roof considerably.

– Buildings with a bird problem have to be cleaned, painted, and repaired more often.

• Droppings will also eat into the protective coatings on automobiles, boats, and airplanes.

Protecting Against Bird Bombs

• Bird droppings are very acidic (pH 3.5 to 4.5).– When they fall on your paint, the acid begins to

burn and etch the paint surface.

– The longer the bird droppings remain, the greater the damage.

• To limit the damage when you get hit, you need to remove the offending slime as quickly as possible. Don't wait.

Birds: Pigeons Control

• The number of pigeons that occupy an area depends upon the availability of food, space, and shelter.

• If some pigeons are shot or poisoned, more pigeons will only take their place, bringing the flock back to its original size.

• Any successful method of bird control must concentrate on prevention and making the location inhospitable to birds.

Birds

• PollyNet can be used to exclude birds of all sizes from problem areas that would be difficult to protect with other bird control methods.– Strong, lightweight netting is made of UV

stabilized polypropylene, making it tough and durable, yet inconspicuous from normal viewing distances.

– It can be easily installed on, over, or around an extensive list of openings, objects and structures.

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RoostingBirds

• Called "porcupine wire" these stainless steel strips are the most effective and the longest lasting bird and animal barrier.

The End