A population viability analysis on the declining population of Little Owl (Athene noctua) in Denmark using the stochastic simulation program VORTEX

Andersen, Line H.; Sunde, Peter; Loeschcke, Volker; Pertoldi, Cino
July 2015
Ornis Fennica;2015, Vol. 92 Issue 3, p123
Academic Journal
When a bird population is facing extinction, ecologically artificial conservation actions such as feeding and captive breeding may be considered as temporary efforts to rescue the population remains until environmental conditions for a self-sustaining population have been restored. Population viability analysis can be used to evaluate different management options for endangered bird populations. Here we use the program VORTEX to explore different management strategies using the Danish population of Little Owl (Athene noctua) as a model species. The Little Owl is declining in several countries, including Denmark, where lack of food during the breeding season has been identified as the main reason for the decline. Four scenarios were run, simulating 25 years of population dynamics: (1) "do nothing" scenario, (2) captive breeding scenario where individuals are supplemented to the population, (3) food supplementation or habitat improvement scenario and (4) scenario combining captive breeding and food supplementation/habitat improvements. In scenarios where no management actions were taken the population went extinct within 12 years. When supplementing individuals continuously the population remained extant but the population size remained small. Food supplementation/habitat improvements can restore the population, though there must be capacity to secure food/habitat for a minimum of 100 individuals to minimize genetic losses. By combining food supplementation and the release of captive bred individuals, the population has a chance of being restored and become independent of human aid. This study exemplifies how management scenarios can be used to guide managers to make informed decisions.


Related Articles

  • Monitoring of the Steppe Eagle Populations in the Trans-Border Zone of Russia and Kazakhstan in 2012. Karyakin, I. V.; Kovalenko, A. V.; Barashkova, A. N. // Raptors Conservation;2013, Issue 26, p61 

    The article is based on the results of monitoring of the Steppe Eagle (Aquila nipalensis) populations in the Orenburg district in Russia and in the Aktobe district in Kazakhstan in 2012. A total of 373 breeding territories of the Steppe Eagles have been examined during the field season 2012; 606...

  • Twenty-Five Years Ago in The Connecticut Warbler.  // COA Bulletin (Connecticut Ornithological Association);Winter2019, Vol. 34 Issue 4, p10 

    No abstract available.

  • An Assessment of Factors Affecting Population Growth of the Mountain Plover. Dinsmore, Stephen J.; Wunder, Michael B.; Dreitz, Victoria J.; Knopf, Fritz L. // Avian Conservation & Ecology;Jun2010, Vol. 5 Issue 1, p1 

    Effective conservation measures should target the most sensitive life history attributes of a species, assuming they are responsive to potential management actions. The Mountain Plover (Charadrius montanus) is a species of conservation concern with a patchy breeding distribution in western North...

  • BREEDING COLONIAL WATERBIRDS. Drilling, Nancy // South Dakota Conservation Digest;Jul/Aug2009, Vol. 76 Issue 4, p12 

    The article discusses conservation efforts and controversies surrounding waterbird colonies in South Dakota. The risk of dense groups of birds nesting in limited locations and the suggested depletion of fish populations by feeding activities of large waterbirds such as pelicans and herons are...

  • Population Decline of the Island Loggerhead Shrike (Lanius ludovicianus anthonyi) in the California Channel Islands. Hicks, Julia J.; Walter, Hartmut S. // Wilson Journal of Ornithology;Mar2009, Vol. 121 Issue 1, p184 

    The Island Loggerhead Shrike (Lanius ludovicianus anthonyi) is classified as a species of special concern by the California Department of Fish and Game. We conducted a breeding bird census of Loggerhead Shrikes on Santa Cruz Island in 2006 based on potential shrike habitats identified using...

  • GENETIC DIVERSITY OF THE CRITICALLY ENDANGERED PHILIPPINE EAGLE PITHECOPHAGA JEFFERYI (AVES: ACCIPITRI DAE AND NOTES ON ITS CONSERVATION. Luczon, Adrian U.; Fontanilla, Ian Kendrich C.; Ong, Perry S.; Basiao, Zubaida U.; Sumaya, Anna Mae T.; Quilang, Jonas P. // Journal of Threatened Taxa;9/26/2014, Vol. 6 Issue 10, p6335 

    The Philippine Eagle Pithecophaga jefferyi is a diurnal raptor endemic to the Philippines. Its distribution is restricted to remaining forests on the islands of Luzon, Samar, Leyte and Mindanao. The Philippine Eagle is classified as a Critically Endangered species under the IUCN Red List, with a...


    Swainson's Warbler (Limnothlypis swainsonii) is a species of conservation concern because of its small wintering range in the Caribbean Basin, relatively low population densities, and habitat fragmentation in its core breeding range in the southeastern United States. We investigated...

  • Review of the Modern Population Status of the Steppe Eagle in the World and in Russia. Karyakin, I. V. // Raptors Conservation;2013, Issue 26, p22 

    There is the analysis of distribution and number of the Steppe Eagle (Aquila nipalensis) nowadays and in the past. The reduction in numbers and the breeding range (especially in its western part) of the species. Modern number of the Steppe Eagle population in the world is estimated at 53-86...

  • Reassessment of the size of the Scopoli's Shearwater population at its main breeding site resulted in a tenfold increase: implications for the species conservation. Defos du Rau, Pierre; Bourgeois, Karen; Thévenet, Mathieu; Ruffino, Lise; Dromzée, Sylvain; Ouni, Ridha; Abiadh, Awatef; Estève, Roger; Durand, Jean-Patrick; Anselme, Lorraine; Faggio, Gilles; Yahya, Jaber; Rguibi, Hamid; Renda, Michel; Miladi, Bayrem; Hamrouni, Hennabaal; Alilech, Slim; Nefla, Aymen; Jaouadi, Wahbi; Agrebi, Sofiene // Journal of Ornithology;Oct2015, Vol. 156 Issue 4, p877 

    Scopoli's Shearwater ( Calonectris diomedea) is a Procellariiform endemic to the Mediterranean Basin which is considered to be vulnerable in Europe due to recent local declines and its susceptibility to both marine and terrestrial threats. In the 1970s-1980s, its population size was estimated at...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics