Lecture 56 Hawaii’s Biodiversity

Environmental Diversity Extremely wide range of habitats temperature moisture soils vegetation

Environmental Diversity Cold & Dry Cool & Dry Warm & Wet Hot & WetHot & Very Dry Warm & Very Dry Warm & Dry trades inversion

Facts: 2,500 miles of ocean separate North America from the Hawaiian Islands. 3,500 miles of ocean between the small Marianas Islands and the Hawaiian chain. The Hawaiian chain has never been connected to a land mass.

How then, did plants and animals cross the large oceanic distance to arrive on the Hawaiian islands? Transportation through the air Attached to Birds Fruits eaten by Birds Drifting in Seawater

Hawaii’s Flowering Plants Long Distance Dispersal Wind, Water, & Wings Theory The original colonist plants arrives in the following ways: water23% wind2% birds75%

14.3% of native flowering plants adapted to oceanic drift. Adaptations for dispersal in seawater: Seeds or fruits capable of floating. Seeds or plant parts must be able to resist seawater for weeks. Must arrive alive on beach and be able to grow there. Pandanus tectorius

Includes plants that reproduce by means of spores such as ferns, mosses, algae, and lichen Spore size: Spores so small that a line of a thousand of them end-to-end would be an inch long. Fern spores would be more successful at reaching Hawaiian island then seeds of flowering plants. Adenophorus periens

1.4% of the 255 hypothetical original flowering plants were dispersed by air flotation Ohia lehua tree has seeds small enough to suggest dispersal through the air. 1 st to appear after a lava flow Metrosideros polymorpha

Insects. Passive flight and small body size of insects accounts for their dispersal to the island. Yellow-faced bee Nesoprosopis pollinates

Embedded in mud on feet or other parts of birds Sticky substances Mechanical devices (barbs, hooks, bristles) Pacific golden plover

Most effective means of seed dispersal to the Hawaiian Islands. Accounts for dispersal of an estimated 39% of the 255 hypothetical original plants. Tetraplasandra flynii Has hairy gray fruits

migration Flowering Plant Dispersal by Birds

Birds Travel through active flight such as migratory birds, marine birds, shore birds and waterfowl. Land birds underrepresented. Insects Passive flight and small size Storms Air currents Migration

Fish Freshwater fish, gobie family (diadromous or amphidromous)) Drift as larvae (long-lasting stage) Marine inverts Drift as larva Ocean currents and gyre Most from Northwest Pacific Islands act as stepping stones

Amphidromous- migrate to and from the sea but do not use the ocean for reproduction

Anchialine pond

Immigration Rates numberrate (1 every …) flowering plants thousand years insects thousand years land snails251.2 million years land birds152 million years mammals130 million years

Biodiversity Number of species Native (got here “naturally” or evolved here) Endemic (found only here) Alien (exotic, human introduction)

NATIVE Occurring naturally in a given geographic area; not introduced as a consequence of human activities Turkey fish

ENDEMIC Occurring exclusively in a given geographic area, having originated in that area through natural means. Hawaiian Cleaner Wrasse

Hawaiian Honeycreepers

Hawaiian Crickets

Pueo

Hawaiian Hawk (Io)

Hoary Bat ( Opeapea )

Hawaiian Monk Seal

Unusual Insects & their Relatives Happy Face Spider

Tree Snails

Nene

Ohia Lehua

Hapu Ferns

Percent Endemism in the Hawaiian Islands

EXOTIC Introduced to a given geographic area as a consequence of human activities. Anemone fish

Speciation Flowering Plants 9% of immigrants adaptive radiation new species migrant species

Results of Speciation colonistsspeciesradiation flowering plants insects ,72281 land snails23-241, land birds radiation = maximum species from 1 colonizing species

Gaps in Speciation Metrosideros polymorpha (ohia) 1 tree species dominates Fills many ecological roles Ordinarily, there would be many species

Metrosideros polymorpha

Honeycreepers No woodpeckers (recently introduced?) No hummingbirds Gaps in Speciation

No native large herbivores Plants with: No thorns (berries) No stingers (nettles) No chemical defenses (mint) Gaps in Speciation

How do they arrive? Dispersal Methods: Rafting Hitchhiking Currents Storms Migrating Islands

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

Polynesian Voyagers to Hawaii taro breadfruit kava yam

Ahupua’a 1.Upland 2.Plains 3.Ocean Ranges from the tip of the mtn to the reef area 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 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

Caribbean frog coqui

Feral pigs Originally introduced by Polynesian voyagers from the Marquesas Islands ca. 400 AD

Two Piranhas were caught in Lake Wilson in There may be more. We don’t know. Piranhas

Jackson’s Chameleon

Brahminy “Hawaiian” Blind Snake Introduced 1930’s Eats ants and beetles Parthogenic Not a threat

Introduced Species Acanthophora, Eucheuma, & Gracillaria

Super Sucker to the Rescue!

Mangroves in Hawaii (transplanted in 1902)

Brown Tree Snake, Guam

Upside-down Jellyfish

Snowflake Coral

Samoan Crab 7 lbs 7 oz, 0/27/09 windward side

Blue stripped snapper

Forest Recovery 1903 = First forest reserve Goal: water conservation For the welfare and development of agriculture Include all non-agricultural lands 1,057 plant species introduced

‘50s: Koa forests burned to plant alien pine trees ‘60s: Ohia forest defoliated by military ‘70s: Bulldozed ohia for alien tree plantations ‘80s: Burn ohia for “bio-power” Forest Recovery

Volcanoes National Park Created 1916; expanded 1927 Cattle grazing for 100 years Cattle eat koa; park concerned Complaints in ‘30s; no action Grazing ended in 1938 Cattle out in 1940 WW II: Grazing again (‘42-’48)

Volcanoes National Park 1927: goat control started 5 years: 17,000 goats removed 1938: 5,000 goats removed Goat proof fence: 70 sq. mi. area 25 years: 25,000 removed Finally: Park is goat-free

Hawaii’s Extinction Crisis Birds and Plants Hawaii as % of US land area0.2% native species14% endangered28% extinct73%

Human Impacts 4, ,000 alien plants About 1,000 naturalized (reproducing naturally) Introductions cause: Competition Harbor diseases Deplete resources

Factors Reducing Habitat Crop lands Cattle grazing Feral animals (cattle, pigs, goats, sheep, deer) Urbanization

1500 years ago dry forest shrubland grassland dry forest shrubland grassland mesic forest shrubland wet forest

1991 developed lands and non-native vegetation developed lands and non-native vegetation

Solutions? Conservation Mechanical (physical removal) Chemical (pesticides, herbicides) Biological (natural predator) Legislation Education Prevention Ballast water: * UV light * chemicals * dump water far from port

Conservation Protection National Parks Nature Conservancy Preserves State Natural Areas Reserves State Parks

Alien Animal Control > $40,000/mile to fence Haleakala NP = $5 million Hard to eradicate animals Animal control not popular

PETA: snares are “in-humane” Few pigs survive > 24 hours Pigs learn how to evade dogs and hunters Hunting doesn’t always kill Dog injury (prohibited?) Pig Control: the Controversy

Lots of misinformation Who speaks for the native vegetation, insects, birds? Pig Control

Introduced grasses a problem Fountain grass in Kona area After fires, fire-adapted species become abundant Helicopters = $700/hour Fire

Fountain grass

Introduces weeds Clean boots before hiking Activities breaking vegetation Creates a path (water, erosion) people/month = major disturbance Human Activity

Specific diseases or pests for weeds Lantana: Introduced ~170 years ago Mynah birds spread seeds 1900: was a major pest 22 insects introduced; 12 established Biological Control

Lantana camara

Rigorous testing before introduction No viruses; highly specific 1st on mainland; repeated here Takes 7 to 8 years Must learn to rear control About 50% success Biological Control

About $500,000/year Hard to get $ for herbicides; easy for biological control

Public Attitudes “Goat eradication program” Negative public reaction “Native ecosystem restoration program” Positive public reaction

“Exotic” “Alien” Introduced Species Yellow ginger

1.What are the two ways in which plants and birds are able to travel the long-oceanic distance to the Hawaiian islands by drifting through the air? 2.How can plants and animals be dispersed to the Hawaiian islands by attachment to birds? 3.What accounts for the largest means of seed dispersal to the Hawaiian islands than any other mechanism? 4.What adaptations must a plant or seed have for dispersal by flotation in seawater? 5.What advantage does “rafting” play in dispersal? Inquiry

6. Two of the major environmental factors influencing Hawai`i's habitat diversity are: 7. The most likely way that flowering plant species arrived in Hawai`i was by: 8. If a species is referred to as being endemic to Hawai`i, you can assume that it: 9. The main reason that Hawai`i's native species don't have thorns, stingers or chemical defenses is that they: Inquiry

10. The removal of cattle from Oahu's forests was important to: 11. There are about _____ native flowering plant species in Hawai`i and _____ introduced ones that are now naturalized. 12. The control of pigs in Hawai`i's forests is: Biological control in Hawai`i has been: Inquiry

13. What class of vertebrates did not arrive to Hawaii by natural means? 14. Compare a generalist exotic species to a specialist. 15. What 2 species have impacted the great lakes and how did they arrive? 16. Why are pigs such a problem? Endemic, Native or Exotic? A B C D E F G Carnivorous caterpillar Cane toad Mushroom coral Green turtle Bottlenose dolphin Blue stripped snapper