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Hawaii’s Biodiversity. …and invasive species problem. ENDEMIC Occurring exclusively in a given geographic area, having originated in that area through natural means. Hawaiian Cleaner Wrasse. Nene. Rare Endemic Birds. Hawaiian Honeycreepers. Pueo. Hawaiian Hawk (‘ Io ). Tree Snails.
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Hawaii’s Biodiversity …and invasive species problem
ENDEMIC Occurring exclusively in a given geographic area, having originated in that area through natural means. Hawaiian Cleaner Wrasse
Nene Rare Endemic Birds
Tree Snails Pūpū Kani Oe
Unusual Insects & their Relatives Happy Face Spider nanana makakiʻi
Hawaiian Monk Seal `Ilio-holo-i-ka-uaua
Most Unique Plants ‘ahinahina Silversword
NATIVE Occurring naturally in a given geographic area; not introduced as a consequence of human activities
EXOTIC Introduced to a given geographic area as a consequence of human activities. Anemone fish
What are some ways that animals arrive at their new location?
How do they arrive? • Dispersal Methods: • Rafting • Hitchhiking • Currents • Storms
Invasive Species Pathways Purposeful introduction via legal and illegal means; Unintentional introduction • Aircraft and cargo ship hulls • Ballast water and ship cargo • Hand-carry/luggage • Agriculture experiment stations • Mail • Forestry activities • Horticulture trade • Aquaculture • Pet trade • Botanical gardens
WHY SOME INTRODUCTIONS SUCCEED AND SOME DON’T? • Disadvantages due to new environmental conditions: • Foraging & predator avoidance strategies may be different • Small #’s of orgs introduced may go extinct • Advantages: • Generalist vs specialist species
Environmental Diversity Extremely wide range of habitats temperature moisture soils vegetation
Environmental Diversity Cold & Dry Cool & Dry inversion trades Warm & Dry Warm & Wet Warm & Very Dry Hot & Very Dry Hot & Wet
water 23% wind 2% birds 75% Long Distance Dispersal Wind, Water, & Wings Theory The original colonist plants arrives in the following ways: Hawaii’s Flowering Plants
Drifting in Seawater Pandanus tectorius Ipomoea pes-caprae
Drifting in Air Includes plants that reproduce by means of spores such as ferns, mosses, algae, and lichen . Adenophorus periens
Attached to Birds Estimated 12.8% of the hypothetical original flowers arrived this way Pacific golden plover Tetraplasandra flynii Has hairy gray fruits
Immigration Rates number rate (1 every …) flowering plants 272 110 thousand years insects 275 110 thousand years land snails 25 1.2 million years land birds 15 2 million years mammals 1 30 million years
Polynesian Voyagers to Hawaii yam breadfruit taro kava
Ahupua’a Ranges from the tip of the mtn to the reef area • Upland • Plains • Ocean Slash & burn agriculture (swidden)
Hawaii Bird Biodiversity Crisis • Half of Hawaii’s native birds went extinct soon after the Polynesians arrived • Half of the remaining species of birds went extinct soon after Captain James Cook arrived
European Contact Large herbivores introduced Native plants are “ice cream” Animals multiplied rapidly
Introduced Feral Mammals Goats 1.5 million skins 1844-1900 Fainting goats Tree goats
Introduced Feral Mammals Cattle on Oahu Wandered Honolulu streets On all land but residential, agricultural or dense forest
Mongoose • Brought in to help control rat population in sugar cane fields • Rat nocturnal • Mongoose diurnal • Mongoose, dogs, and cats are the nene’s main predator
Poison dart frog Coqui frog coqui coqui coqui
Feral pigs Originally introduced by Polynesian voyagers from the Marquesas Islands ca. 400 AD
Pig Fence Pig wallow