Embed Size (px)
Citation preview
GRASSHOPPER MANAGEMENTGRASSHOPPER MANAGEMENTIN NEW MEXICOIN NEW MEXICO
Train-the-Trainers Workshop presented by Train-the-Trainers Workshop presented by Alexandre Latchininsky and Scott Schell,Alexandre Latchininsky and Scott Schell,
UW Extension EntomologistsUW Extension Entomologists
Sponsored by: USDA-APHIS-PPQSponsored by: USDA-APHIS-PPQ
DisclaimerDisclaimer• Trade or brand names used in this Trade or brand names used in this
presentation are used only for presentation are used only for the purpose of educational the purpose of educational
information.information. • No product endorsement is No product endorsement is implied.implied.
Workshop Principle:
Everybody is ignorant, Everybody is ignorant, only on different subjects only on different subjects
-- Will Rogers-- Will Rogers
OrOr
I don’t know everything and neither do you, I don’t know everything and neither do you, so let’s learn from each otherso let’s learn from each other
(a.k.a. – when I’m wrong, let me know)(a.k.a. – when I’m wrong, let me know)
Workshop “Rules”
It’s called a It’s called a workworkshop on purposeshop on purposeAsk any question, at any timeAsk any question, at any time
Be a Be a constructiveconstructive skeptic skeptic
What animal is the primary What animal is the primary above-ground herbivore above-ground herbivore
in a grassland biome in a grassland biome in North America?in North America?
Role of GrasshoppersRole of Grasshoppers in a Prairie Ecosystemin a Prairie Ecosystem
•Natural “mowers” stimulate plant growthNatural “mowers” stimulate plant growth
•Nutrient cyclingNutrient cycling
•Food for many prairie animalsFood for many prairie animals
Biology of the Species of Concern Biology of the Species of Concern
Grasshoppers may be an important component in Grasshoppers may be an important component in the diet of Sage Grouse chicksthe diet of Sage Grouse chicks
Snakeweed grasshopperSnakeweed grasshopper Cudweed grasshopperCudweed grasshopper
Weed Biocontrol Agents?Weed Biocontrol Agents?
Some Grasshoppers Some Grasshoppers AREARE Beneficial! Beneficial!
Plains LubberPlains Lubber EbonyEbony
TwostripedTwostriped RainbowRainbow
DiversityDiversity>450 species in N.A.>450 species in N.A. ≈≈17170 species in NM0 species in NM
PESTS!PESTS!
BIOLOGY & ECOLOGYBIOLOGY & ECOLOGYTaxonomyTaxonomy
Class: Class: InsectaInsectaOrder: Order: Orthoptera (22,500 species; Orthoptera (22,500 species;
1,015 – in N. America)1,015 – in N. America)
Close relatives:Close relatives: Blattodea (Cockroaches)Blattodea (Cockroaches)Mantodea (Praying Mantises)Mantodea (Praying Mantises)Dermaptera (Earwigs)Dermaptera (Earwigs)
TaxonomyTaxonomy
Order OrthopteraOrder Orthoptera
Suborder CaeliferaSuborder Caelifera Suborder EnsiferaSuborder Ensifera
(short-horned)(short-horned) (long-horned) (long-horned)
GrasshoppersGrasshoppers KatydidsKatydids
NOT GrasshoppersNOT Grasshoppers
katydidskatydidscricketscrickets
Straight ovipositorStraight ovipositor
Curved ovipositorCurved ovipositor
Mormon cricketMormon cricketis neither a grasshopper is neither a grasshopper
nor a cricket…nor a cricket…
……it’s a A KATYDID!it’s a A KATYDID!
Anabrus simplexAnabrus simplex
Grasshopper TaxonomyGrasshopper Taxonomy
Family: Family: AcrididaeAcrididae
Subfamilies:Subfamilies: -- Melanoplinae (spurthroated),Melanoplinae (spurthroated),- Gomphocerinae - Gomphocerinae
(slantfaced), (slantfaced), - Oedipodinae - Oedipodinae (bandwinged),(bandwinged), - Romaleinae - Romaleinae (lubbers),(lubbers),
- Cyrtacanthacridinae (bird - Cyrtacanthacridinae (bird grasshoppers)grasshoppers)
Genera: Genera: ≈70≈70 in New Mexico in New Mexico
Species: Species: ≈≈171700 in New Mexico, in New Mexico,
>450>450 in Western US in Western US
GRASSHOPPER PESTS GRASSHOPPER PESTS IN THE WESTIN THE WEST
- - economically important in 17 western stateseconomically important in 17 western states
- 20-25 pest species (out of >450)- 20-25 pest species (out of >450)
- annually remove 20-22% of rangeland vegetation- annually remove 20-22% of rangeland vegetation
- estimated average loss $400 million per year- estimated average loss $400 million per year
- forage losses in 2000 in Texas: $190 million- forage losses in 2000 in Texas: $190 million
- require vast areas to be chemically treated - require vast areas to be chemically treated (up to 20 million acres per year during (up to 20 million acres per year during outbreaks)outbreaks)
What to Expect in 2006?What to Expect in 2006?Rangeland Grasshopper Hazard MapRangeland Grasshopper Hazard Map
20052005 20062006
Grasshopper BiologyGrasshopper Biology
All you need to know in order to get All you need to know in order to get rid of unwanted dinner guestsrid of unwanted dinner guests
final molt
egg-pod
nymphal instars 1 to 5~ 30-40 d~ 30-40 d
egg-laying
Life cycle
mating
flights
1st instar - critical stage for GH survival (up to >90% mortality)
DevelopmentDevelopment
• One generation per year One generation per year = univoltine= univoltine
• Oviposition mostly in soilOviposition mostly in soil
• 1-4 egg-pods per female1-4 egg-pods per female
• 5-40 eggs per egg-pod5-40 eggs per egg-pod
Twostriped grasshopperTwostriped grasshopper
Grasshopper Egg-podsGrasshopper Egg-pods
Biology & EcologyBiology & Ecology
Seasonal DevelopmentSeasonal Development
Typical:Typical: - hatching in spring- hatching in spring- nymphal and adult development - nymphal and adult development in summerin summer- overwinter as eggs- overwinter as eggs
Some species:Some species: - overwinter as late-instar nymphs- overwinter as late-instar nymphs- adults in early summer (usually, - adults in early summer (usually, band-winged species)band-winged species)
Development: Gradual MetamorphosisDevelopment: Gradual Metamorphosis
11
2233
44
55
Nymphal instars: 5 (rarely 4)Nymphal instars: 5 (rarely 4)
AdultAdult
11
22
33 44
55
Developmental stagesDevelopmental stages
AdultAdult
Nymphal development: 26-40 days (~1 wk/instar)Nymphal development: 26-40 days (~1 wk/instar)
Clearwinged grasshopperClearwinged grasshopper
Nymph or Adult?Nymph or Adult?
NN
NNAA
AA
Wing VenationWing Venation
NYMPHNYMPH ADULTADULT
No cross veinsNo cross veins A lot of cross veinsA lot of cross veins
Physiology and BehaviorPhysiology and Behavior
Feeding:Feeding: Herbivores (necrophily & scavenging)Herbivores (necrophily & scavenging)
50% of total consumed by adulthood50% of total consumed by adulthoodAdults: feeding on flowers and seedsAdults: feeding on flowers and seedsFeeding is “constant” in assemblageFeeding is “constant” in assemblage
Movement:Movement: Primarily walking (1-3 m/day upwind)Primarily walking (1-3 m/day upwind)
Flight for escape and dispersalFlight for escape and dispersalMigration due to crowding and geneticsMigration due to crowding and genetics
Biology & EcologyBiology & Ecology
Biology & EcologyBiology & Ecology
Food Preferences & Feeding HabitsFood Preferences & Feeding Habits
Grass feeders:Grass feeders: Slantfaced and many Bandwinged Slantfaced and many Bandwinged species (species (Aulocara, Ageneotettix, Camnula, ArphiaAulocara, Ageneotettix, Camnula, Arphia) )
Forb feeders:Forb feeders: many Spurthroated species ( many Spurthroated species (Melanoplus Melanoplus foedusfoedus, , M. angustipennis, Hesperotettix viridisM. angustipennis, Hesperotettix viridis))
Mixed feeders:Mixed feeders: many Spurthroated species ( many Spurthroated species (Melanoplus Melanoplus sanguinipes, M. bivittatus, M. differentialissanguinipes, M. bivittatus, M. differentialis). ). Truly polyphagous; high economic importanceTruly polyphagous; high economic importance
Mormon cricket: may feed on >400 plants but prefers forbsMormon cricket: may feed on >400 plants but prefers forbs
1 in
1 ¾ in
Comparative sizeComparative size
TwostripedTwostripedfemalefemale1.1 g1.1 g
ClearwingedClearwingedfemalefemale0.6 g0.6 g
In a habitat, grasshopper population In a habitat, grasshopper population consists of several (usually 5-20) speciesconsists of several (usually 5-20) species
Often, 1-4 species occupy a predominant Often, 1-4 species occupy a predominant position accounting for >50% of total position accounting for >50% of total grasshopper populationgrasshopper population
AssemblagesAssemblages
Biology & EcologyBiology & Ecology
Clearwinged grasshopperClearwinged grasshopper
Population DynamicsPopulation Dynamics
Normally:Normally: Grasshopper dynamics are Grasshopper dynamics are regulated by abiotic regulated by abiotic (weather) and (weather) and biotic (natural enemies) factors, but biotic (natural enemies) factors, but if they if they fail… fail…
……Outbreaks!: Outbreaks!: Last for 1-4 yrs, occur at irregular Last for 1-4 yrs, occur at irregular intervals - every 4-10 intervals - every 4-10 yrsyrs
Warm/dry conditions in the Warm/dry conditions in the summer are summer are particularly particularly favorable for outbreaksfavorable for outbreaks
Anthropogenic effects (overgrazingAnthropogenic effects (overgrazing and insecticides)and insecticides)
Biology & EcologyBiology & Ecology
•Slower developmentSlower development•More susceptible to More susceptible to diseases and diseases and natural natural enemiesenemies•Higher mortalityHigher mortality•Less eggs producedLess eggs produced
Less damagingLess damaging
Weather: Direct and Indirect EffectsWeather: Direct and Indirect Effects
•Faster developmentFaster development
•Less susceptible to diseases and Less susceptible to diseases and natural enemiesnatural enemies
•Lower mortalityLower mortality
•More eggs producedMore eggs produced
More damagingMore damaging
Weather: Direct and Indirect EffectsWeather: Direct and Indirect Effects
Population DynamicsPopulation Dynamics
Spatial:Spatial: -- Outbreaks clumped in spaceOutbreaks clumped in space
- Association with static features - Association with static features (e.g.,(e.g., soil type)soil type)
- May spread from localized “hot - May spread from localized “hot spots”spots”
Biology & EcologyBiology & Ecology
Biology & EcologyBiology & EcologyNatural EnemiesNatural Enemies
PredatorsPredators
Natural EnemiesNatural Enemies• Egg predatorsEgg predators
Diptera BombyliidaeDiptera Bombyliidae
Bombyliidae larvaeBombyliidae larvae
Blister Blister beetlesbeetles
• Internal parasites (nematodes)Internal parasites (nematodes)
Grasshopper parasitized Grasshopper parasitized with a mermithid nematodewith a mermithid nematode
Nematode egg Nematode egg and larvaand larva
Natural EnemiesNatural Enemies
• ParasitoParasitoidsids
Wasp Wasp Scelio sp.Scelio sp., , Egg parasitoidEgg parasitoid
Flies (Muscidae, Tachinidae)Flies (Muscidae, Tachinidae) Parasitoids of nymphs and adultsParasitoids of nymphs and adults
Natural EnemiesNatural Enemies
Predator “saturation”Predator “saturation”
Biology & EcologyBiology & EcologyBionomicsBionomics
Damage:Damage: Primary concern is rangelandPrimary concern is rangeland
Movement into cropland is relevantMovement into cropland is relevant
Control:Control: Economic Injury Level =Economic Injury Level =
= Damage > = Damage > Treatment costTreatment cost
Economic Threshold = Economic Threshold = = 20, 3rd-4th instars per sq. yd= 20, 3rd-4th instars per sq. yd
Variation with timing, species, efficacy, cost, Variation with timing, species, efficacy, cost, etc.etc.
BionomicsBionomics
Other:Other: Cultural (grazing, plowing, planting)Cultural (grazing, plowing, planting)
Mechanical (crushing)Mechanical (crushing)Integrated Pest ManagementIntegrated Pest Management
Future:Future: Fewer external resources with moreFewer external resources with more
environmental concern, economic demands,environmental concern, economic demands,people, need for control, and changepeople, need for control, and change
Biology & EcologyBiology & Ecology
Purpose of ManagementPurpose of Management
Emerging Philosophy:Emerging Philosophy:
The purpose of grasshopper management is The purpose of grasshopper management is to keep good stewards on the land – to keep good stewards on the land –
to keep those people who live to keep those people who live withwith the the Land, Land, onon the Land. the Land.
National Grasshopper Management BoardNational Grasshopper Management Board
Integrated Pest Integrated Pest ManagementManagement
IPM is an approach that substitutes IPM is an approach that substitutes knowledge and information for materials knowledge and information for materials and external inputs:and external inputs:
Essential components:Essential components:
Monitoring Monitoring Decision-makingDecision-makingMethods & MaterialsMethods & Materials
The 3-Phase The 3-Phase Approach toApproach toGrasshopper Grasshopper
IPMIPMEndorsed by the National Grasshopper Management BoardEndorsed by the National Grasshopper Management Board
Prevention:Prevention: Range management practices Range management practices
(“twice over” livestock grazing) (“twice over” livestock grazing) have been shown to yield have been shown to yield
habitat conditions that both:habitat conditions that both: produce more forageproduce more forage andand yield yield
fewer grasshoppersfewer grasshoppersTwice-overTwice-over vs. 5-month season-long vs. 5-month season-long grazinggrazing::
~300 lbs/acre more herbage biomass~300 lbs/acre more herbage biomass 66 to 75% reduction in grasshopper populations66 to 75% reduction in grasshopper populations
BUT,BUT,IfIfPreventionPreventionfails …fails …
Intervention:Intervention:
Efficient survey combined with Efficient survey combined with treatment of incipient infestations treatment of incipient infestations or “hot-spots” has been shown toor “hot-spots” has been shown to
prevent the expansion of prevent the expansion of grasshopper infestations into grasshopper infestations into
large-scale outbreakslarge-scale outbreaks
BUT,BUT,IfIf
InterventionIntervention
fails …fails …
Suppression:Suppression:
The use of The use of Reduced Agent-Area TreatmentsReduced Agent-Area Treatments after analysis with CARMA allows after analysis with CARMA allows
rangeland grasshopper control to yield:rangeland grasshopper control to yield:
significant economic profitssignificant economic profits
withwith
minimal environmental harmminimal environmental harm
Putting the “I” in Putting the “I” in IPMIPM
PreventionPreventionsurvey/sampling + cultural controlsurvey/sampling + cultural control
InterventionInterventionsurvey/sampling + decision support (forecasting) + survey/sampling + decision support (forecasting) + hot-spot chemical controlhot-spot chemical control
SuppressionSuppressionsurvey/sampling + decision support (economic model) survey/sampling + decision support (economic model) + chemical control + conservation biological control+ chemical control + conservation biological control
Accurate and Timely Survey is Accurate and Timely Survey is Critical for Efficient ControlCritical for Efficient Control
• Grasshopper density Grasshopper density assessmentassessment
• Species compositionSpecies composition
• Developmental stages Developmental stages (age structure of (age structure of population)population)
• Acreage infestedAcreage infested
• Egg-bed locationEgg-bed location
