Insect Conservation. Biodiversity. Insect conservation 4/16/2012. Insects play essential, irreplaceable roles in ecosystems

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1 Insect Conservation Biodiversity Insects are by far the most successful organisms on this planet There are more kinds of insects than any other group of organisms Insects dominate in terms of numbers of species and in numbers of individuals every ecosystem on Earth, except marine ecosystems Insects play essential, irreplaceable roles in ecosystems 1) Nutrient recycling 2) Plant pollination 3) Maintenance of plant community composition and structure t 4) Maintenance of animal community structure 5) Supporting insectivorous animals Insect We know a few species well (pests), but we know little or nothing about most beneficial or neutral insects 1

2 Insect extinctions Approximately 11,200 species have gone extinct since the year Some scientists estimate that ½ million to 40 million species may go extinct in the next 300 years. Insect extinctions Challenges Only about 10% of all insects have scientific names People don t often care to conserve insects. Butterflies are an exception! In U.S., threats to imperiled species are: (Wilcove et al. 1998) Threats to insects Percent Impe eriled (%) Vertebrates Mammals Birds Reptiles Amphibians Fishes Habitat loss Exotic species Pollution Overexploitation Disease Habitat destruction Pollution (environmental contamination) I i i Invasive species Side effects of classical biological control Genetic engineering Global climate change 2

3 Habitat destruction The Population Bomb: Growth is not the same in different countries: But, neither is the per-capita consumption of resources Wealthy countries (like the USA) often do much more harm to the environment than poor countries! The United States, with less than 5 % of the global population, uses about a quarter of the world s fossil fuel resources burning up nearly 25 % of the coal, 26 % of the oil, and 27 % of the world s natural gas. We cannot blame the developing world for environmental problems. Education and health care help to reduce population growth rates in poor countries. Most children in the world live in poverty. What we may consider a normal childhood (below) is actually not normal. 3

4 4/16/2012 Habitat loss and disturbance (examples as of 1991) Forest Wetland/Marshes Mexico 66% U.S. 54% Argentina 50% New Zealand 90% India 78% Australia 95% Grassland Desert/Scrub U.S. ~99% India 88% New Zealand 90% Pakistan 69% Prior to European colonization, more than half of Florida's original landscape was comprised of wetlands. In recent years, Florida's increasing population and growing need for homes, agriculture and industry have led to the rapid destruction of wetland regions, areas previously misunderstood as wastelands. By 2003, nearly half of Florida's original wetlands have been severely altered, or destroyed. Wetland alteration adversely affects native species, disrupts flood pattern, degrades water quality, and threatens numerous freshwater habitats that depend on wetlands. Source: University of Florida, IFAS Extension Habitat loss and disturbance (examples as of 1991) Forest Wetland/Marshes Mexico 66% U.S. 54% Argentina 50% New Zealand 90% India 78% Australia 95% Grassland Desert/Scrub U.S. ~99% India 88% New Zealand 90% Pakistan 69% Habitat destruction in the USA: 99.9% of tallgrass prairie has been destroyed Natural Iowa Historic Iowa Landscape mid 1800 s Current Iowa Landscape

5 4/16/2012 Rocky Mountain locust, Melanoplus spretus Rocky Mountain locust, Melanoplus spretus The grasshoppers ate and ate; they devoured everything from barley and buckwheat to spruce and tobacco. The locusts even ate blankets that women put over the crops to protect them. A few records report the locusts eating fence posts, leather, dead animals, and sheep wool. Cannibalism was also observed. One common comment was that grasshoppers ate everything but the mortgage (Evans, 1966; Atkins, 1984). Rocky Mountain locust, Melanoplus spretus Habitat destruction in the USA: 99.9% of tallgrass prairie has been destroyed So abundant in the Midwest of North America in the late 1800s that it caused the wheels of locomotives to slip By 1906 it was extinct. Most likely the extinction occurred from destruction of their breeding grounds (native prairie). Historic Iowa Landscape mid 1800 s Current Iowa Landscape 1996 Remains recently collected from a glacier. Habitat destruction in the tropics Probably more than half of all insects live in tropical forests 130,000 square km are lost annually. Threats to insects Habitat destruction Pollution Invasive species Side effects of classical biological control Genetic engineering Global climate change 5

6 Pollution Pollution Insect species will be affected differently some will do fine, others will perish. Insecticides often kill or reduce fitness of non-pests Invasive species Cane toad in Australia eating everything! Mosquitofish in Hawaii were introduced to eat mosquito larvae, but are now causing problems for local l damselflies Invasive species mice and rats Invasive mice and rats commonly decimate invertebrate populations on islands Lord Howe Island stick-insect Driven locally extinct by rats Big-headed ant Argentine ant Fire ants Invasive species ANTS! Problems with classical biological control What is classical biological control? Introduction of foreign biological control agents to control foreign pests Outcompete local ants and can devastate local insect faunas 6

7 Problems with classical biological control Cactoblastis cactorum What is classical biological control? Introduction of foreign biological control agents to control foreign pests Mistakes can be made!! Genetic Engineering May enhance pesticide resistance Otherwise, not enough is known yet Global Climate Change Species will need to move, evolve the ability to handle new conditions, or they may go extinct. Specialists may have a hard time moving over fragmented landscapes! How can we prioritize land to preserve? Insect planning ~Global Scale~ Biodiversity hotspots From the following article: Biodiversity hotspots for priorities Norman Myers, Russell A. Mittermeier, Cristina G. Mittermeier, Gustavo A. B. da Fonseca and Jennifer Kent Nature 403, (24 February 2000) 7

8 Biodiversity hotspots Threats to insects Habitat destruction Pollution (environmental contamination) Invasive species Side effects of classical biological control Genetic engineering Global climate change 1. Maintain reserves as source habitats 2. Maintain as much quality landscape heterogeneity as possible Source Sink 3. Reduce contrast between remnant natural patches and neighboring disturbed areas Contrast between forest and farmland 8

9 3. Reduce contrast between remnant natural patches and neighboring disturbed areas 4. Outside reserves, maintain as much undisturbed habitat as possible (landsparing) Conservancy Reserve 5. In transformed landscapes, simulate natural conditions and disturbance Fires in North-Central Florida Florida has the highest rate of lightning strikes per year than anywhere in U.S.A. Fire was frequent here Habitat t around Gainesville ill is firedependent. Oaks are common due to fire suppression. 6. Connect like patches of quality habitat as much as possible 9

10 6. Connect like patches of quality habitat as much as possible Studies show that many insects move along corridors of remnant indigenous vegetation Combine habitat approach with species-focused approaches Since we cannot save them all, which species should we choose to save? Icaricia icarioides fenderi, Fender's Blue Butterfly Zaitzevia thermae, Warm Springs Zaitzevian Riffle Beetle Found in only 35 square meters special hot springs habitat in Montana. Less than 1000 remain Worth saving? Found only in the upland prairies of the Willamette Valley in western Oregon Possibility of extinction remains high due to their small population p size, expansive habitat degradation, and succession. 10

11 Somatochlora hineana, Hine's Emerald Dragonfly Only known dragonfly endangered in U.S.A. Habitat destruction poses the greatest single threat to them Other dragonflies have been helped by farm dams. They provide the necessary habitat for dragonflies that would normally inhabit natural wetlands. 11