Where Have All the Birds Gone?

Written on |

Humans Behind Extinction of Hundreds of Bird Species Over the Last 50,000 Years.

A new study from Tel Aviv University and the Weizmann Institute revealed that over the last 20,000-50,000 years, birds have undergone a major extinction event, inflicted chiefly by humans, which caused the disappearance of about 10%-20% of all avian species. The vast majority of the extinct species shared several features: they were large, they lived on islands, and many of them were flightless.

The main cause for extinction of species by humans today has evolved from being hunting to the destruction of the animals’ natural habitats, but the researchers hope their findings will serve as warning signals regarding bird species currently threatened with extinction.

The study was led by Prof. Shai Meiri of the School of Zoology at The George S. Wise Faculty of Life Sciences and the Steinhardt Museum of Natural History at Tel Aviv University, and Amir Fromm of the Weizmann Institute of Science. The paper was published in the Journal of Biogeography.

Human-Inflicted Extinction

Prof. Meiri: “We conducted a comprehensive review of scientific literature, and for the first time collected quantitative data on the numbers and traits of extinct species of birds worldwide. Those that became extinct in the last 300 years or so are relatively well known, while earlier species are known to science from remains found in archaeological and paleontological sites worldwide. Altogether we were able to list 469 avian species that became extinct over the last 50,000 years, but we believe that the real number is much higher.”

The researchers believe that the vast extinction was caused primarily by humans who hunted the birds for food, or by animals brought to islands by humans – that fed on the birds and/or their eggs. This assumption is based on the fact that the greater part of bird remains was found on human sites, apparently belonging to birds consumed by the inhabitants, and in most cases the extinctions occurred shortly after the arrival of humans.

Coveted Targets for Hunters

Most extinct species shared three major features:

  1. About 90% of them lived on islands – When humans arrived on the island, the birds were hunted by them, or fell victim to other animals introduced by humans, such as pigs, rats, monkeys, and cats.
  2. Most extinct bird species were large, some very large – The body mass of the extinct species was found to be up to 10 times as large as that of surviving species. The larger birds provided humans with a great quantity of food, thus they were a preferred target for hunters. Previous studies have found a similar phenomenon among mammals and reptiles, especially lizards and turtles that lived on islands: the larger ones were hunted by humans and became extinct.
  3. A large portion of the extinct bird species were flightless, and often unable to escape their pursuers – The study found that the number of flightless bird species that became extinct is double the number of flightless species still existing today; all in all, 68% of the flightless bird species known to science became extinct. One of the better-known examples is the moa bird in New Zealand: 11 species of moa became extinct within 300 hundred years, due to hunting by humans

Prof. Meiri: “Our study indicates that before the major extinction event of the past millennia, many more large, even giant, as well as flightless avian lived on our globe, and the diversity of birds living on islands was much greater than today. We hope that our findings can serve as warning signals regarding bird species currently threatened with extinction, and it is therefore important to check whether they have similar features. It must be noted, however, that conditions have changed considerably, and today the main cause for extinction of species by humans is not hunting but rather the destruction of natural habitats.”

Featured image: Bird species at the Zoological Garden

related posts

Tel Aviv Bats Have More Fun

July 22, 2021

The survivability of animal species depends on the number of offspring rather than body size

June 10, 2021

First-of-its-kind study: Researchers used smart watches to monitor changes in quality of life during lockdowns

June 8, 2021

Bats ‘Social Distance’ Too

June 6, 2021

Time Flies and So Do Bats

May 31, 2021

When One Becomes Three

May 19, 2021

Fireflies’ Protective ‘Musical Armor’ Against Bats

May 12, 2021

An Underwater Salute to Grandma Vera

April 8, 2021

Struggling in a Toxic Workplace?

April 6, 2021

Robot “Hears” through the Ear of a Locust

March 4, 2021

An Underwater Journey Following the Vanishing of Sponge Species from the Shallow Water of the Israeli Coast

December 1, 2020

Why Do Bats Fly Into Walls?

November 10, 2020

Pharmaceutical residuals pose a serious threat to Marine life

August 19, 2020

Bats navigate just like humans – using their excellent eyesight and a cognitive map

July 12, 2020

TAU researchers discover unique, non-oxygen breathing animal

February 26, 2020

Coral danger: breakdown in spawning could mean extinction

September 11, 2019

Pope welcomes Israeli, Jordanian, Palestinian bird experts

June 11, 2019

Inside a bat’s brain

February 13, 2019
Ontario and Western Canada

3130 Bathurst Street, Suite, 214, Toronto, ON | M6A 2A1 
Phone: 416.787.9930 | Toll Free: 833.32.CFTAU (22328)
Email: toronto@cftau.ca

Ottawa, Quebec and Atlantic Canada

6900 Boulevard Décarie, Suite 3480, Montreal, QC | H3X 2T8
Phone: 514.344.3417
Email: montreal@cftau.ca


© CFTAU  | all rights reserved
Charitable registration: 124035643RR0001

TO TOP