Brown Bear, Mexican Grizzly Bear, Grizzly Bear
Be (II); CITES (II); RDBUkr: Зникаючі
Value of species
Game (hunting) species
The brown bear is the most widely distributed ursid. It once ranged across a large portion of North America, including northern Mexico (plus, at one time, much of the eastern half of the continent), throughout Europe, Asia, the Middle East, and even across North Africa. It presently occupies approximately 5,000,000 km² of the northwestern portion of North America, 800,000 km² of Europe (excluding Russia), and much of northern Asia. The largest numbers exist in Russia, U.S. (Alaska), and Canada. Many populations in Europe, and the more southerly portions of Asia and North America are small and isolated (Servheen et al. 1999, Swenson et al. 2000). A history of prolonged over-exploitation in Europe stretching back centuries resulted in the elimination of brown bears from many countries. The date of their extirpation from North Africa is uncertain, but they may have existed as late as the 1500s in the Sinai of Egypt (Manlius 1998) and mid-1800s in Algeria and Morocco (Hamdine et al. 1998). During the 20th Century, brown bears (called grizzly bears in interior North America) were extirpated in Mexico and a large portion of southwestern U.S. (Brown 1985, Mattson and Merrill 2002), while in Asia and the Middle East they have apparently been eliminated from Syria, and possibly Bhutan. Very small numbers of brown bears still remain in Iraq and Nepal (Gurung 2004, Ridings 2006). Andorra was reoccupied in 2003 from bears reintroduced into the French Pyrenees. A few wandering individuals recently crossed into Switzerland from Italy and into Lithuania from Latvia and Belarus, but not enough as yet to be considered extant populations.
The brown bear currently occurs in Afghanistan, Albania, Andorra (recently reoccupied), Armenia, Austria, Azerbaijan, Belarus, Bhutan (possibly extinct), Bosnia and Herzegovina, Bulgaria, Canada, China, Croatia, Czech Republic (possibly only vagrants), Estonia, Finland, France, Georgia, Greece, India, Iraq, Islamic Republic of Iran, Italy, Japan, Kazakhstan, Democratic People’s Republic of Korea, Kyrgyzstan, Latvia, the Former Yugoslav Republic of Macedonia, Mongolia, Montenegro, Nepal, Norway, Pakistan, Poland, Romania, Russian Federation, Serbia, Slovakia, Slovenia, Spain, Sweden, Tajikistan, Turkey, Turkmenistan, Ukraine, United States, and Uzbekistan. The species has become Extinct during past 500 years in Algeria, Egypt, Germany, Hungary, Israel, Lebanon, Liechtenstein, Lithuania, Mexico, Moldova, Morocco, Palestinian Territory (Occupied), Portugal, San Marino, Switzerland, and Syrian Arab Republic. Extinctions due to human agency have taken place more than 500 years ago in Belgium, Denmark, Ireland, Jordan, Luxembourg, Monaco, Netherlands, Tunisia, United Kingdom, and the Vatican.
The total world population of brown bears is estimated to exceed 200,000. Reliable population estimates (derived mainly from mark-recapture or resight, and modifications thereof) exist for several areas in North America and Europe (Miller et al. 1997, Swenson et al. 2000, Bellemain et al. 2005, Mowat et al. 2005), but few areas in Asia. Russia has the largest number of brown bears, believed to exceed 100,000, while estimates in the U.S. are around 33,000, Canada 25,000, and Europe (excluding Russia) 14,000.
Brown bears occupy a great variety of habitats from dry Asian steppes to Arctic shrublands to temperate rain forests. Their range overlaps that of both the American and Asiatic black bear (U. americanus, U. thibetanus), and also slightly that of the polar bear (U. maritimus). Elevationally they range from sea level to 5,000 m asl (Sathyakumar 2006). They occupy a greater diversity of habitats than any other species of bear and also exploit a large variety of food items. In terms of diet, they fall between the mainly plant-dependent ursids and the carnivorous polar bear (Mattson 1998, Sacco and Van Valkenburgh 2004). In North America, brown (grizzly) bears are more carnivorous where ungulates (especially in Arctic areas) or spawning salmon (coastal areas) are abundant (Mowat and Heard 2006).
The productivity and density of brown bears varies enormously, corresponding with the productivity of their habitats. Coastal areas of North America and Eastern Russia, with concentrations of spawning salmon, have high densities (>10 bears per 100 km²) of brown bears (Miller et al. 1997, Seryodkin 2006) with high reproductive rates (Hilderbrand et al. 1999). Deciduous and mixed forests of the Dinaric and Carpathian mountain ranges of Eastern Europe also host high bear densities with high reproductive rates (Kusak and Huber 1998, Frković et al. 2001). More moderate densities of bears occur across the interior mountain ranges of North America (McLellan 1994, Schwartz et al. 2003), Europe, and Asia where they forage on a great variety of grasses, herbs, roots, berries, nuts, as well as animal matter such as insects, mammals, and fish if available. Moderate densities of bears are also found across portions of the boreal forests of North American, Asia and Scandinavia (Bellemain et al. 2005). Lower densities are found in dry, desert-like areas, alpine and sub-alpine areas, as well as areas where habitat availability and numbers of bears have been reduced by high human and domestic livestock densities (Nawaz 2007); however, in most such areas (e.g., northern India, western China, Mongolia) density estimates are not available.
Breeding occurs during May to July but implantation of the blastocyst is delayed until late autumn. Cubs, usually in litters of 1 to 3 (rarely 4 or more), are born in January or early February when the mother is hibernating. In North America, female bears generally have their first litters at 5 to 8 years of age and have litters every 3 or 4 years thereafter (Schwartz et al. 2003). In some areas of Europe, however, females generally have their first litter at least one year earlier, and produce litters every two years (Swenson et al. 2000, Frković et al. 2001).
- Татаринов К. А. Звірі західних областей України (матеріали до вивчення фауни Української РСР). - Київ: Вид-во АН УРСР, 1956. - 188 с.