mass extinction
Since the dawn of civilization, starting with the megafauna extinction, humanity has killed 83% of all wild animals and 50% of all plants. 70% of all the birds in the world today are chickens or other farmed poultry. [5] Wildlife populations have declined by 68% since 1970. [6] Freshwater populations have declined by 84%. [7] [8]
The International Union for Conservation of Nature’s Red List of endangered species includes 41% of the world’s amphibians, â…“ of all conifer trees, ¼ of all mammals, and â…“ of coral reefs. [9]
Percentage of local population extinction in 177 species of mammals in 1° × 1° quadrats, as an indication of the severity of the mass extinction crises. The maps were generated by comparing historic and current geographic ranges. Note that large regions in all continents have lost 50% or more of the populations of the evaluated mammals. Because of the small sample size, biased to large mammal species, this figure can only be used to visualize likely trends in population losses. [10]
Relative frequency of major threats by taxonomic group - Threat data is available for 3,789 populations in the global LPI database. Each of these populations could be associated with up to three different threats. There were 6,053 threats recorded in all. [6]
Predicted net loss of local species richness for 2090 using the PREDICTS framework Net loss is shown for the ‘business-as-usual’ scenario, based on a pre-human baseline. Data derived from Newbold et al., 2015. [86]
Background extinction rates are 1000 times higher than normal. [11]
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The biomass of all insects on the planet is decreasing by 2.5% per year. 40% of all insect species are threatened with extinction. [12]
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Plants are going extinct 350 times faster than the historical norm. [13] [14]
The number of domesticated and farmed animals has skyrocketed. [15] The Amazon rainforest is not being clear-cut for lumber, but rather for grazing land for cattle. [16]
In the 1970s and 1980s, Atlantic cod was severely overfished. [17] In spite of fishing having ceased, cod stocks have yet to recover. [18] The Gulf of Alaska fishery closed for the first time in 2019 due to lack of fish, and millions of sea birds have died as a result. [19]
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​There also exist vast, illegal fishing fleets that turn off their transponders so they can’t be tracked. [20] 1 in 5 fish are caught illegally. A quarter of all fish caught globally is caught using bottom-trawling which destroys the seabed. [21] Up to 14% of the seabed is actively being trawled. [22] Illegal fishing could be the catalyst for a conflict in the South China Sea. [23]
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Distant-water fishing fleets abuse their crews with excessive overtime, withheld wages, and verbal and physical abuse. A report by the Environmental Justice Foundation on Tawainese fishing fleets found that 50% illegally catch sharks, 14% catch dolphins for bait or to sell, and 11% catch false killer whales. [72] [73]
Average annual catches of the world’s maritime fishing countries in the 1950s compared to the 2000s - Blue indicates zero or very minute catches, and yellow indicates light or no fishing. Zones of moderately heavy (in orange) to heavy fishing intensity (in red) now wrap around every continent, affecting all coastal areas and many parts of the high seas. Maps generated by the Sea Around Us information system. [6]
Percentage change in fish abundance between 1997 and 2003 in marine reserves and on open reefs. Percentage change is calculated from the average of the first two surveys (1997–1998) and last two surveys (2002–2003) for all fish species in the families Acanthuridae, Chaetodontidae, Labridae, and Pomacentridae. The numbers on the x axis represent individual species (1–77) and are ranked from largest increase to largest decline for open reefs. Only species with a mean number per transect >1 are included, most showing a statistically significant change over time. Two surgeonfish species (marked by an asterisk) showed an increase in marine reserves relative to fished reefs. [27]
It may already be too late to do anything to save the world’s coral reefs. [24] At 1.5°C, 70% of coral reefs are expected to undergo annual bleaching events. [56] Marine “dead zones” are also developing thanks to the sheer amount of fertilizer we dump into the oceans. [25]
Fertilizers cause massive (and toxic) algal blooms. When the algae dies and sinks in the ocean, microbes breaking down the algae use-up all the oxygen in that water column, producing anoxic “dead zones” that lack oxygen. These zones are expanding far quicker than we thought. [26] The more we lose our topsoil to overfarming, the more fertilizer we put in the soil, which runs off into the oceans, exacerbating this problem.
Degradation of coral reefs. a) Results of a meta-analysis of the literature, showing a decline in coral cover on the Great Barrier Reef. Each point represents the mean cover of up to 241 reefs sampled in each year. b) The recorded number of reefs on the Great Barrier Reef, Australia, substantially damaged over the past 40 yr by outbreaks of crown-of-thorns starfish (COTS) and episodes of coral bleaching. [28]
The fastest growing corals take 10 years to regrow, but coral bleaching events are happening too quickly in succession for populations to recover. [24]
Frequency of occurrence of harmful algal blooms [in the Indian EEZ] during the last century. Eighty algal blooms were recorded during the period 1998–2010. Of the eighty algal blooms, 31 blooms were formed by dinoflagellates, 27 by cyanobacteria, and 18 by diatoms. [29]
Shark populations are estimated to have declined by 71% since 1970. [225]