Biodiversity

Source: Huffington Post

Biodiversity refers to the diversity within species (genetic diversity), between species (species diversity), and between ecosystems (ecosystem diversity). A study published in 2018 in the PNAS 1 determined that the 7.6 billion population of the earth represents just 0.01% of all living things, but has caused the loss of 83% of all wild animals and half the plant life on earth. Three centuries of whaling have left only a fifth of marine mammals in the oceans.

As the apex predator, humans have been destroying other mammalian species at a dramatic rate, meaning that it will take 5 to 7 million years to regain the biodiversity that existed before modern humans. Up until 45,000 years ago, Australia was abundant with large mammals, but with the arrival of humans that population collapsed within just a few thousand years.2

Today, farmed poultry makes up 70% of all birds on the planet. 60% of all mammals are livestock, mostly cattle and pigs. The destruction of wild habitat has resulted in what is being referred to as the sixth mass extinction. The difference between this event and previous extinctions, however, is the time scale. What took thousands of years, heretofore, is now happening at an unprecedented rate with about half of the earth’s animals thought to have been lost in the last fifty years.3

It’s not just mammals, a new term has entered the environmental jargon recently, “Insect Apocalypse.” A recent study from Germany reports that the flying insect population has dropped over 75% since 1989.This rate of extinction is eight times faster than that of mammals, birds, and reptiles and is being driven by the heavy use of herbicides and pesticides in large scale agriculture. In the tropics, rising temperatures are thought to be a contributing factor in the decline.

Ecological scientists consider this a serious problem because “…insects are at the heart of every food web, they pollinate the large majority of plant species, keep the soil healthy, recycle nutrients, control pests, and much more. Love them or loathe them, we humans cannot survive without insects.”5

Source: CMS.INT

The devastation continues in the oceans. Climate change is rapidly warming the seas where the creatures living there are more vulnerable than land based species. Accustomed to a very stable temperature environment, some may be able to move, but others like corals and sea anemones cannot and will die. As has been the case on land, human activity has dramatically reduced the amount of wilderness areas in the oceans.  Destructive fishing  practices like trawling are producing significant declines in ocean wildlife populations with the number of over-fished stocks having tripled in the last 50 years.

To make matters worse, the oceans are polluted with oil, trash, fertilizer and pesticide runoff, and more than 8 million tons of plastic every year. A significant but under-reported story is that noise pollution in the seas is a huge problem. Sound waves travel farther and faster in water than in the atmosphere. The continual din produced by military sonar, oil exploration, and industrial shipping create an invisible threat to marine wildlife. This can be especially harmful to whales and their keen sense of hearing sometimes even killing them.

UN IPBES Report on Biodiversity and Ecosystem Services, May 6, 2019

The first global biodiversity assessment since 2005 provides a grim, bleak study of what humans have done to the biosphere with a focus on the last 50 years. The devastation has been immense with the great majority of ecosystem and biodiversity indicators showing rapid decline. Across the planet, “ecosystems, species, wild populations, local varieties and breeds of domesticated plants and animals are shrinking, deteriorating or vanishing.”6

The report lists and ranks the five most significant drivers of these changes in descending order:

  • changes in land and sea use
  • direct exploitation of organisms
  • climate change
  • pollution
  • invasive alien species

Global interconnectivity is responsible for “resource extraction and production occurring in one part of the world to satisfy the needs of distant consumers in other regions.” This facilitates the myopia of responsibility. The depressing numbers in the report are myriad and can be found by reading the 39 page Summary for Policymakers available here:

https://www.ipbes.net/sites/default/files/downloads/spm_unedited_advance_for_posting_htn.pdf

The report also makes it clear that humans are dependent on the health of our ecosystems for our very existence. 

The War on Wolves in America

Wolves are an important part of the ecosystem, but they are being hunted and killed at a rate that threatens to return them to near absence in America. This killing is facilitated by federal and state agencies including the US Fish and Wildlife Service at the behest of ranchers seeking to protect their cattle. Idaho, Montana, and Wyoming allow trophy hunters, trappers, and ranchers to kill wolves.

Acting Secretary of the Interior David Bernhardt announced as of March 2019 that wolves will be delisted from the endangered species list. As one of the great stories of species recovery this is an incredibly regrettable commentary on what really matters in America: Sacrificing wolves to produce more meat – one of the most environmentally damaging processes in our system of food production.

The Center for Biological Diversity is fighting these developments. If you love wolves:

https://www.biologicaldiversity.org/

The Marine Food Web

The most important organism in the ocean ecosystem is phytoplankton (plankton), a small microbial which lives near the surface. It is instrumental in maintaining climate balance as it absorbs CO2 and produces about two-thirds of the planet’s oxygen via photosynthesis. When the plankton die, they sequester the CO2 into deep waters for thousands of years, in this way limiting global warming. 

It is also the base of the marine food system. Without it, fish populations would die and commercial fishing would disappear. Warm oceans, however, contain less oxygen and, therefore, less plankton. They move to cooler waters and take the fish that feed off of them with them. Small fish and some larger fish and whales consume phytoplankton as their main food source. Whales then fertilize the plankton when they defecate. Restoring whale populations would be an important step in rejuvenating plankton.

Phytoplankton has diminished by about 40% since 1950. Yet, Japanese and Norwegian commercial fishing corporations, which continue to kill whales, also take millions of tons of plankton to produce protein-rich animal feed. 40% of all fish caught today is converted to fishmeal to feed pigs, chickens, domestic salmon, fur bearing animals, and cat food. As the fish diminish because of over-fishing, these corporations are looking to replace it with plankton paste. (Yes, that means robbing the oceans of oxygen producing organisms in order to make feed for meat producers.) Plankton populations are also damaged by pollution, including plastics and agricultural runoff, and air blasts for ocean oil exploration, 

As the foundation of the marine food web, even apex predators like sharks are dependent on the ecological base formed by plankton. Every year there is a huge outcry when someone dies because of a shark attack. However, rarely is it mentioned that every year humans kill an estimated 100 million sharks. Many millions are killed for their shark fin and then tossed back into the seas where they will die. Sharks have been a part of the marine ecosystem for 450 million years, but they are now threatened with extinction. The oceans, however, are dependent on them to help balance the ecosystem. Their absence would threaten a much larger diversity of life. As the apex marine predator, they limit the abundance of their prey affecting other species throughout the food chain. They also help to preserve seagrass meadows by preventing turtles from overgrazing these areas. Their presence prevents smaller predators from dominating coral reefs where herbivores are useful in eating the algae which would overgrow the reefs.

From whales to sharks to plankton: it is an ecosystem dependent on the smallest organism.