1. Competition including introduced species
> 80% Island Fox population decline in recent years, primarily caused by Golden Eagle predation and introduction of canine disease
In 1883 mongooses to the Big Island to control rats in sugar cane fields.
Also eat lizards, crabs, toads, frogs, birds and bird eggs, fish, spiders, and the grubs of beetles and caterpillars …everything!

2. Disease - diverse community slows spread
Grape phylloxera Daktulosphaira vitifoliae
Infection causes premature defoliation, reduced shoot growth, reduced yield and poor quality of the crop.
Grape phylloxera, Daktulosphaira vitifoliae (Fitch), is a serious pest of commercial grapevines worldwide. This tiny insect forms galls on leaves and roots of grapevines. It is believed that this insect originated in the Eastern United States, where damage is now most prevalent on leaves of French-American hybrid grapevines. High populations of foliar phylloxera can result in premature defoliation, reduced shoot growth, and reduced yield and quality of the crop.
Feeding by root phylloxera on European grapevines, Vitis vinifera L., is potentially devastating and nearly destroyed the French wine industry in the late 1800's. The epidemic was eventually brought under control by grafting V. vinifera scions onto resistant American, Vitis labruscana Bailey, rootstocks. A major resistance breeding program conducted in Europe against grape phylloxera resulted in grape cultivars commonly referred to as French-American hybrids. French-American hybrids are important in eastern North America for wine production, but they are particularly susceptible to foliar grape phylloxera. Widespread planting of French-American hybrids in eastern North America has resulted in a heightened awareness of foliar phylloxera. Foliar phylloxera reduce net photosynthesis of grape leaves. Leaf galling by grape phylloxera causes distortion, necrosis, and premature defoliation of French-American vines. Premature defoliation may delay ripening, reduce crop quality, and predispose vines to winter injury. Grapevines heavily infested with foliar phylloxera may contribute to root infestations. Research indicates that high population densities of foliar phylloxera can result in a reduction in yield and quality of the crop. Populations must reach very high densities before yield is affected, and in most years yield will probably not be affected. It is not known, however, what impact infestations by the insect year after year have on the overall health and vigor of the vine.
Control
Few chemicals are registered for control of foliar grape phylloxera.

3. caused by the fungus Phytophthora ramorum
Sudden Oak Death
caused by the fungus Phytophthora ramorum
Fungal; 107 susceptible host plants. Infected California bay laurels are the most effective spreaders of the deadly microbe, but such common garden ornamentals as camellias and rhododendrons can also spread the disease to oaks.
known to spread in water and has been detected in numerous waterways, including the Crystal Springs Reservoir. Garbelotto believes heavy rains over the past two years caused the sudden jump in the infection rate reflected in the study this year.
Central CA – southern OR ,000’s trees killed
Perhaps as many as 90 % of California's live oaks and black oaks could die from the disease within 25 years.

4. Since 1990, bark beetles have spread, killing millions of trees across millions of hectares of forest from Alaska to southern California
Climate Change
Since 1990, native bark beetles have killed millions of trees across millions of hectares of forest from Alaska to southern California. Although bark beetle infestations are a regular force of natural change in forested ecosystems, several of the current outbreaks, occurring simultaneously across western North America, are the largest and most severe in recorded history. The recent large-scale dieback of piñon (Pinus edulis Engelm.) and ponderosa pine (P. ponderosa Dougl. ex Laws.) and associated bark beetle outbreaks in the Southwestern United States has been linked to the ”climate change type drought” (e.g., dry and warm) Larva are cold-susceptible; as warming happens, the species (200+) spread.

5. SO WHAT?
"It is reckless to suppose that biodiversity can be diminished indefinitely without threatening humanity itself."
Edward O. Wilson