R I College of Agricultural, Consumer and Environmental Sciences T F All About Discovery! ™ New Mexico State University aces.nmsu.edu Integrated Wildlife Damage Management: For Master Gardeners in New Mexico Master Gardeners 2018 Samuel T. Smallidge Wildlife Specialist Cooperative Extension Service The College of Agricultural, Consumer and Environmental Sciences is an engine for economic and community development in New Mexico, improving the lives of New Mexicans through academic, research, and extension programs. Outline Introduction Species 1. Pocket gophers 2. Squirrels 3. Skunks 4. Rabbits 5. Snakes 6. Birds 7. Bats http://aces.nmsu.edu/pubs/_L www.icwdm.com Integrated Wildlife Damage Management Principles of Wildlife Management Appropriate use Follow label Check local, state, and federal laws/regulations. Humane dispatch “An ounce of prevention is worth a pound cure.” Multiple and Integrated Methods 2 FUNDAMENTAL STRATEGIES HABITAT MANAGEMENT Food Water Shelter POPULATION MANAGEMENT Direct Indirect △N = +B +I –D –E Wildlife Damage Management Steps to Consider: (1)Define and identify problem; • What is the damage? Quantify amount ($). Identify species. Cost-benefit analysis (2) Understand problem species; • Nocturnal or diurnal? Carnivore or herbivore? Migratory? (3) Evaluation of control method(s); (4) Apply control method(s). (5) Monitor progress & adapt effort accordingly MONITORING “if you can’t monitor it, you can’t manage it” -old adage from old unknown source BIOLOGICAL YEAR Integration NO CONTROL Habitat Mod. Exclusion Baiting CONTROL Fumigation Harassment CONTROL Repellants CONTROL Trapping Shooting Pocket Gophers in NM Yellow-faced pocket gopher (Cratogeomys castanops) Botta’s pocket gopher Northern pocket gopher Southern pocket gopher (Thomomys bottae) (Thomomys talpoides) (Thomomys umbrinus) Plains pocket gopher Desert pocket gopher Jones pocket gopher (Geomus bursarius) (Geomys arenarius) (Geomys knoxjonesi) Pocket Gophers Illustrations and distributions courteous Smithsonian Museum of Natural History Gopher Burrow System Burrow systems:1-2 main tunnels;4 to 18 in. below surface; lateral burrows for foraging, defecating, nesting, food cache. Rate of mound building highly variable; R.O.T. ~ 1 to 3/day, up to 70/month; correlated with rainfall; quickly seal openings 6-8/acre OR 63 may = high densities Illustration courtesy of Nebraska Cooperative Extension Gopher Damage Consume roots of saplings (pos. girdle) Tunnels divert water Undermine irrigation infrastructure Gnaw water lines Damage equipment if burrows collapse Potential Gopher Benefits Increase soil fertility by adding organic matter Soil cycling – 1 t/y Increase soil aeration and decrease soil compaction Increase water infiltration Gopher Habitat Modification • remove weeds to create an unsuitable buffer strip • mechanical or chemical modification • adjacent to areas experiencing consistent damage Planting 50-foot buffer strips of grain around hay fields to discourage gopher immigration Flooding - In garden, try marigolds, narcissus, and daffodils Gopher Exclusion Expensive and has limited practicality Fence valued ornamental shrubs or trees • 1/4 or 1/2 inch hardware cloth buried at least 18-24 inches (Drawings by Jenifer Rees.) Finding the tunnels Locate main runway Find freshest mound 4-12 in. behind plug 15 to 18 inches from mound Patience, skill, experience key Finding Gopher Tunnels Illustrations courtesy of the University of California Cooperative Extension Fumigants • aluminum phosphide (RUP): effective • gas cartridges (nRUP): not as effective efficacy related to soil moisture. Fumigants Prohibited: residential properties, nursing homes, schools (except athletic fields), day care facilities, and hospitals. within 100 feet of a building that is or may be occupied by people or domestic animals. DANGER/PELIGRO Image of skull and crossbones, DO NOT ENTER/NO ENTRE, FIELD NOT FOR USE name and EPA registration number of the fumigant, & a 24-hour emergency response number. Signs may be removed 2 days after the final treatment. Fumigant Management Plans required Pressurized Exhaust Rodent Control PERC Propane Exploder Mixture of propane and oxygen • Built-in, self contained ignition system ignites mixture creating underground shockwave or concussion • May collapse burrow system Toxic Baits Anticoagulants Acute Diphacinone Zinc phosphide (RUP) (RUP) Chlorophacinone Strychnine (nRUP/RUP) (nRUP/RUP) Multiple feedings Single feedings Bait Applied Underground Follow label Apply rec. amount of bait April-May Late September – Early October Baiting Thorough training ~ doubled efficiency rates for bait applications. 15 min. = 27% efficiency 90 min. = 58% efficiency 1. Ensure bait is in active tunnel (acitve v. backfilled). 2. Regular check application equipment for clogging. Baldwin 2014 Trapping Gophers Effective on small or large infested areas or as supplement control A) Macabee B) Victor C) D-K 1 D) Guardian Trapping Gophers Mound Set & Main Tunnel Set Tunnel no wider than trap-jaw width Trapping Trap all the way in the tunnel Bed the trap Trapping 92% Alum. Phosphide 84% PERC 62% Baldwin et al. 2013a Gophinator > Macabee Covered sets late spring/early summer (no diff. autumn) Covered sets = > T req. (Diff. in captures not enough) Ag. setting don’t cover sets Baldwin et al. 2013b No Sig.Diff. for Peanut Butter, anise, grapefuit essence, carrot w/o attractant - uncovered > covered PB/covered sets yielded heavier pocket gophers (mop-up/breeders) Baldwin et al. 2014 As time affords. Audience Selection Audience Selection 1. Squirrels 2. Skunks 3. Rabbits 4. Snakes 5. Birds 6. Bats http://aces.nmsu.edu/pubs/_L www.icwdm.com Ground Squirrels Rock squirrel (Spermophilus variegatus) NM Thirteen-lined ground squirrel (S. tridecemlineatus) NM Spotted ground squirrel (S. spilosoma) NM Golden-mantled ground squirrel (S. lateralis) NM Antelope ground squirrel (Ammospermophilus spp.) NM Spermophilus lateralis S. spilosoma Ammospermophilus spp. Ground Squirrel Identification • Forage above ground near burrows • 9-11 inches in length (5-9 inches tails) • Variable coloration (grays, blacks, browns, whites) • May look like tree squirrels (& climb trees) – will always seek shelter in burrow. Ground & Tree Squirrels & Chipmunks Illustrations courteous of Smithsonian Museum of Natural History Ground Squirrel Burrows Burrows: Open; multiple entrances (~4” dia.) never plugged with soil at surface (hib./est.) Maybe complex Colonial species Active during day (mid-morning; late afternoon) Ground Squirrel Diet Herbivore/Omnivore OR Omnivore/Herbivore change w/ season green vegetation during growing season Seeds, grains, nuts, fruit (when grasses dry up) Also insects, bird eggs, baby mice, carrion Usually forage close to burrow (range 30 – 150+ yds) Ground Squirrel Damage Ag crops (fruits), home gardens, recreational areas, Girdle trees, damage roots (decreased productivity) Gnaw on plastic sprinkler heads, irrigation lines Burrows divert irrigation water, increase erosion Photos courtesy UCD Extension Ground Squirrel Control Control method influenced by life cycle and behavior. Illustration courtesy UCD Cooperative Extension Squirrel Control Methods Exclusion Fences: not practical can dig beneath fences buried several ft deep expensive Sheet metal cylinders around tree trunks Frightening techniques not effective Chemical & odor repellents generally not effective Trapping -Trapping can be effective in reducing low to moderate squirrel populations -Try baiting with banana and/or peanut butter; walnuts, almonds, slice of orange or melon. Fumigants gas cartridges (GUP) CO, CO2, other nail to stir insert fuse & light deep placement & plug burrow entrance ** efficacy related to soil moisture. gas cartridges Squirrel Fumigants Alum. Phosphide (RUP) Gas Cartridges (GUP) Most effective following squirrel emergence from hibernation - before the squirrels reproduce Toxicants Rodenticides labeled for species Read the label Reference label for correct dosage and proper application Consider Non-target risk ZP - Pre-baiting increases efficacy Rodenticide-treated bait hand applied Shooting/Hunting Labor intensive, but potentially effective Shot over squirrels become vary wary Follow local laws (no shooting w/in city limits) Skunks New Mexico is home to the Striped skunk (Mephitis mephitis) Western spotted skunk (Spilogale gracilis) Hog-nosed skunk (Conepatus mesoleucus) Hooded skunk (Mephitis macroura) New Mexico Skunks Spotted Hog-nosed Hooded Striped Variety of habitats: farmland, grasslands, ravines, rocky outcrops, fence lines, woodlots, forest edges. Key is food supply and denning sites/cover. Illustrations and distributions courteous Smithsonian Museum of Natural History Skunk Diet Omnivorous; diet depends on season Feed on insects (beetles, grasshoppers, crickets, grubs) Earthworms, snails, clams, crayfish, frogs Mice, voles, moles, rats, squirrels Bird eggs, carrion, garbage Variety of wild fruits Skunk Populations On average move 0.6-2 miles depending on season and geographic location Densities vary but are highest in early summer as juvenile skunks become active Skunk Diseases Major vector of rabies Account for 20% of rabies cases in the US Skunks with rabies may be extremely docile or exhibit extreme aggression Very susceptible to canine distemper virus, leptospirosis, and infectious canine hepatitis Leptospirosis is a widespread bacterial disease to which humans are also susceptible Skunk Damage Ranging from nuisance to economic damage • Digging in