In just the past 50 years wildlife populations have reduced by an average of 51% . Animal farming and fishing is the leading cause of this decline  and of species extinction generally. Current global species extinction rates are 100 – 10,000 times higher than natural background rates . Animal agriculture fuels the core processes driving this mass extinction:
- habitat loss/degradation ,
- exploitation of wild species ,
- climate change [5; 6],
- hunting of predator and ‘competition’ animals perceived as a threat to ‘livestock’ ,
- the use of pesticides and other chemicals ,
Whilst wildlife used to dominate Earth, humans and domesticated animals now account for 36% and 60% of terrestrial vertebrate biomass . Wildlife therefore only accounts for 4%. Humans have now significantly altered 75% of land-based ecosystems and 66% of marine ecosystems .
At present, the biomass of predatory fish communities has been reduced to roughly 10% of their pre-industrial levels  as their populations are being killed by the fishing industry faster than their populations can recover. The continuation of this trend in fishing could potentially lead to the global collapse of all marine species currently being exploited by 2048 .
Insect populations have also plummeted. Forty percent of insect species are now threatened with extinction . Looking at specific examples, in Costa Rica there has been a 98% decline in ground-dwelling species , and in Germany a 76% decline in flying species . The leading cause of all of this is the loss of habitat , the leading cause of which is animal agriculture .
Insects play a vital role in pollination and are one key example of how declining ecosystem health can have detrimental consequences for humans. More than 75% of the different types of food we eat rely either directly or indirectly on pollination : without pollinators, we risk losing all of these foods.
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