Many species are threatened with extinction due to our actions. The IUCN Red List of Threatened Species collects records of these species, listing their status on a continuum from least concern to extinct.
These are the endangered species I’ve blogged about:
Numbat (Myrmecobius fasciatus) Endangered
There are probably less than 1,000 mature individuals, and the population has undergone a drastic, continuing decline at Dryandra (one of the two native sites for the species), the reasons for which are not understood. The populations at Perup are stable (possibly increasing), and stable, though probably not self-sustaining, at the reintroduced sites. Overall the populations are estimated to have decreased by more than 20% in the last 5 years. 
Thylacine (Thylacinus cynocephalus) Extinct by 1936 due to trapping and shooting by European settlers in Tasmania. An epidemic at the turn of the 20th century decimated the population of Tasmanian devils, and quolls on the mainland, and may have contributed to the thylacine’s extinction . Gary Crew and Mark Wilson provide a haunting rendition of the last thylacine’s captivity at Hobart Zoo in I saw nothing: The extinction of the Thylacine .
- Friend, T. & Burbidge, A. (2008) Myrmecobius fasciatus in IUCN 2009. IUCN Red List of Threatened Species. Version 2009.1. <www.iucnredlist.org>. Downloaded 6 August 2009.
- Tasmanian Dept of Primary Industries and Water (2009) Devil Facial Tumour Disease.
- Rounsevell, D.E. (1983) “Thylacine” in Strahan (Ed.) The Australian Museum Complete Book of Australian Mammals: The National Photographic Index of Australian Wildlife Sydney: Angus & Robertson. pp.81-83.
- Crew & Wilson (2003) I saw nothing: The extinction of the Thylacine Melbourne: Lothian.
- Atkins, K.J. (2008) Declared Rare and Priority Flora List for Western Australia Como, WA: Dept of Environment and Conservation.