Entomology 10

Solitary bee (Andrena) collecting pollen from vernal pool flower (Blennosperma)

Insect Conservation

I. Conservation biology-

II.Political conflicts-

III. Problems convincing public and policy makers to conserve insects

1. Not furry, cuddly critters nor "Charismatic megavertabrates"
2. More often obscure, cryptic
3. Not generally valued
4. Pest image

IV. Why conserve insects?

1. Dominance- "Age of Insects"
   1. Diversity of species
   2. Abundance of individuals
2. Diversity of ecological roles in environment
   1. Trophic levels
   2. Interactions with other species
   3. Base of many food chains/webs
   4. Indicator species ["Miner's Canary"]
3. Potential chemical resources [Chemical prospecting]
   1. Aboriginal medicines
   2. Dyes, Lac, Propolis, Honey, Beeswax
   3. Bioluminescence
   4. Pheromones & Hormones
4. Potential genetic resources
   1. Resistance in beneficial insects
5. Other roles beneficial to humans
   1. Biological control
   2. Pollination
   3. Laboratory animals

V. What should be saved?

1. Rare and endangered or threatened [Endangered Species Act]
2. Keystone species [Critical elements]
3. Flagship species [Showy, aesthetic]
4. Indicator species [Respond to disturbance processes]
5. Evolutionary/Phylogenetic progenitors
6. Habitat
   1. How diverse?
   2. How much? [Area]
7. Single populations
8. Metapopulations
   1. Single populations vulnerable to extinction
   2. Replaced by emigration from adjacent refugia
   3. Genetic diversity
9. Functional species groups ["Drivers" vs "Passengers"]
   1. Several species filling same/similar ecological role

VI. Causes of extinction and population losses

1. Ecological succession
   1. Sequence of temporary stages of communities to stable climax
2. Loss of genetic variability (inbreeding)
3. Loss of habitat (or habitat degredation)
4. Loss of host
5. Invading predators, parasites, competitors
6. New diseases

VII. How can they be saved?

1. Endangered Species Act [1974]
   1. Prohibits unauthorized "Take"
   2. Recovery plans
   3. Critical habitat
2. Umbrella species [Large habitats required, shelter many other species]
3. Habitat preservation (Reserves/Preserves)
4. Management of Reserves/Preserves

VIII. Case Histories:

1. Vernal pool habitat [Jepson Prairie Reserve]
   1. Temporary wetland
   2. Special organisms live in pools
      • Wet: Fairy shrimp, Tadpole shrimp
      • Drying: Delta Green Ground Beetle, Elaphrus viridis
      • Dry: Orcutt grasses
   3. Many showy flowers with pollen host-specific bees as pollinators
      • Yellow carpets [Blennosperma]
      • Goldfields [Lasthenia]
      • Meadowfoam [Limnanthes]
   4. Mitigations
      • Habitat preservation
      • Creation of new pools offsite
      • Ignorance of processes
2. Lange's Metalmark [Apodemia mormo langei] [Antioch dunes, CA]
   1. Listed in 1976
   2. Specialist on Eriogonum [Native buckwheat]
   3. Habitat threatened by development
   4. Reserve established 1980
   5. Recovery attempts- habitat/host plant restoration
3. Large Blue Butterfly [Maculinea arion] [United Kingdom]
   1. Caterpillars depend on host plant (Thyme) and ants
      • Young- feed in flower heads
      • Old- feed on ant brood
   2. Habitat also grazed by rabbits

Readings in Gullan, P.J. and Cranston, P. S. (1994). The Insects: An Outline of Entomology:

• Scan: pp. 2-3 (1.2); pp. 7-10 (1.3); p. 400; p. 417 (12.2.2)

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