Life history Food Distribution Management... 98

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1 BEAR: Table of Contents Overview Life history Food Distribution Management Statistical Reports Controlled spring bear season harvest General season black bear harvest Oregon general bear season and harvest summary

2 Overview Once hunted as a predator and nuisance animal for bounty, the black bear (Ursus americanus) received game mammal status in Since then bear numbers have increased under a more conservative harvest strategy. However, larger bear populations and statutory changes to management alternatives have increased the complexity of bear management. Color of individual black bears may vary greatly and includes many shades of black and brown. Black is by far the most common color in western Oregon. But nearly 3/4 of bears in eastern Oregon have some shade of brown. The preponderance of brown-phase black bears could explain the occasional grizzly bear sightings reported in northeastern Oregon. Bear Life History Black bear breed primarily in June and July and cubs are generally born in the den during January or February during hibernation. Because lactating females do not breed, alternate year pregnancies are typical in black bear. Black bear litter size varies from one to six cubs, with two young per litter most common. In years of poor food production, litter sizes tend to be smaller. Young generally remain with the female for slightly over one year and disperse as yearlings in the spring, when females breed again. Once born, cubs have a relatively high chance of survival; however, all or part of a litter may be lost to factors such as predation, disease, or cannibalism (primarily by adult male bears). If a female loses her litter, she will generally breed the following season. Oregon Department of Fish and Wildlife 3406 Cherry Ave NE Salem, OR Bears are long-lived animals. In Oregon, bears 20 years old and older have been documented. The fact that a number of animals reach this age indicates that adult survival rates are fairly high. However, survival rates may vary by age class, sex and location. Food Because bears must eat and store 12 months worth of energy in only 8-10 months, their behavior is dominated by a desire to fill their stomachs. As a result, bears have a very diverse diet that includes a wide range of plants and animals. Their annual diet consists mostly of plant material, but bears also will scavenge carrion or kill for food. 100

3 When a bear emerges from its den, it seeks any abundant food source to replace body mass lost during hibernation, and to build body reserves in preparation for the coming winter. Bear foraging areas change seasonally. In spring, just after emergence from the den, bears may select open hillsides or clearcuts for foraging, because these areas are the first to green up. In some areas, bears may prey on newborn elk calves and deer fawns when they are vulnerable during the first few weeks of life. As the seasons progress, bears often move to utilize more readily available food resources. Bears seek out berries and nuts when and where available. Moist sites are preferred, regardless of the time of year. Early successional vegetation that occurs following forest disturbances such as timber harvest or fire generally provides desirable food concentrations for bear. As forests mature, food production for bears decreases and animals shift foraging areas to those providing the most desirable grasses, forbs, berries and shrubs. Most desirable for bear management are those timber harvest practices that open extensive dense canopies, increase diversity of the plant species that provide foods for bear, leave trees for escape, and maintain large hollow trees and snags for denning. Bears typically forage at night. However as winter denning approaches, bears may forage more during daylight because of the need to store fat reserves. Additionally, bears may forage more during daylight when food availability is poor (drought, late spring, poor berry crop). Distribution Historically, black and grizzly bears (U. arctos) were both native to Oregon; however, the last grizzly bear documented in Oregon was killed in Wallowa County in Occasionally grizzlies are reported in Oregon but no evidence to substantiate these reports exists. These are likely sightings of light or cinnamon colored black bears. The highest black bear population densities are found in the Coast Range, Siskyou, Cascade, Wallowa, and Blue Mountains. Black bear distribution in Oregon tends to be restricted to forest zones, typifying their preference and need for forest ecosystems. The availability of trees to climb for safety directly influences bear survival (particularly for cubs). Shade provided by forest cover is important to bears for thermo-regulation during hot periods of the year. Stumps and logs are important sources of den sites used for hibernation, birthing, and rearing cubs. Bears tend to prefer heavy cover adjacent to foraging areas for resting. Typically, a bear will hollow out a small bed for resting in a location that is sheltered from environmental extremes. The location of bed sites changes as the bear changes foraging areas. Management Since an annual census of bears is not yet feasible, the department has used other methods of assessing overall population health and the impact of harvest on the population. Monitoring sex and age characteristics of the harvest is biologically sound and used by managers to track trends in overall bear population health, size, and structure. Black bear populations are difficult to estimate because of the animal s secretive nature, relatively low density compared to animals like deer and elk, and their ability to use natural cover. In southwestern Oregon, biologists have been using tetracycline wrapped in bacon to mark bears to estimate the bear population. Once eaten, the tetracycline marks a ring in the teeth similar to a tree ring. Bear teeth submitted by hunters and from bears taken on damage are examined to age the bear and determine if it was marked by tetracycline. Under a microscope and ultraviolet light, the markings on the teeth from the tetracycline can be seen. The ratio of marked to unmarked bears can be used to develop an improved population estimate. In 2005, the bear marking project using tetracycline has been expanded 101

4 from SW Oregon to statewide. In order for the study to be successful and provide accurate estimates of bear populations, it is essential that hunters provide teeth from harvested bears. Black bear population studies in several states (including Idaho, Alaska, and Arizona) indicate that lightly hunted black bear populations have a high percentage of adult males (30 percent or more), a high ratio of adults to sub-adults (60:40 or more), and a median age of four to five years or greater. Heavily hunted populations had relatively low percentages of adult males, adult to sub-adult ratios favoring subadults, and median ages of four years or less. designated collection site within 10 days of the kill to be checked and marked. All data indicates that current harvest levels are not detrimental to bear population structure. In addition, bear damage problems have increased in recent years, indicating a stable or increasing population. A mandatory check-in of all harvested bear is required in Idaho and Montana for the purpose of population analysis. Beginning in 2008, the skull of any bears harvested must be presented to an ODFW office, or 102

5 2009 CONTROLLED SPRING BEAR SEASON HARVEST HARVEST HUNT HUNT HUNTER PERCENT DAYS/BEAR NUMBER NAME TAGS HUNTERS DAYS MALE FEMALE UNKNOWN TOTAL SUCCESS HARVESTED 712A WILSON-TRASK A NORTH CASCADES A ALSEA-STOTT MT A SOUTH CENTRAL HOOD UNIT A SOUTH BLUE MTS A WEST BLUE MTS A STARKEY UNIT WENAHA UNIT T WENAHA UNIT YOUTH A SLED SPRINGS-CHESNIMNUS T SLED SPRINGS-CHES YOUTH A SNAKE RIVER A MINAM-IMNAHA T MINAM-IMNAHA YOUTH A PINE CR-KEATING-CATHERINE CR LOOKOUT MT UNIT LSB LIMITED SW SPRING BEAR SPRING BEAR SEASON TOTALS 7,635 4,718 26,

6 HUNTER HARVEST PERCENT DAYS/BEAR UNIT/AREA HUNTERS DAYS MALE FEMALE UNKNOWN TOTAL SUCCESS HARVESTED WESTERN OREGON 2009 GENERAL SEASON BLACK BEAR HARVEST NORTHWEST 4,526 59, SOUTHWEST 5,043 62, CASCADES 8,964 98, WESTERN OREGON TOTAL 18, ,

7 HUNTER HARVEST PERCENT DAYS/BEAR UNIT/AREA HUNTERS DAYS MALE FEMALE UNKNOWN TOTAL SUCCESS HARVESTED EASTERN OREGON 2009 GENERAL SEASON BLACK BEAR HARVEST EASTERN OREGON TOTAL 11, , STATEWIDE TOTALS 29, ,

8 OREGON GENERAL BEAR SEASON AND HARVEST SUMMARY TAGS HARVEST HUNTER HUNTER DAYS/ DAYS/ YEAR SEASON DATES AREA SOLD HUNTERS MALE FEMALE UNKNOWN TOTAL SUCCESS DAYS HUNTER BEAR 1975 July 01-Dec. 31/ Coast & NE Aug. 01-Nov. 30 Entire State 17,924 16, ,841 11% 148, Aug. 01-Dec. 31/ Coast & NE Aug. 01-Nov. 30 Entire State 14,660 11, ,074 10% 102, Aug. 01-Dec. 31/ Coast & NE Aug. 01-Nov. 30 Entire State 15,847 12, % 133, Aug. 01-Dec. 31 3/4 of State 8,770 1 No Survey Sep. 01-Nov. 30 3/4 of State 15, , % 118, Aug. 23-Nov. 30 Entire State 14, , % Aug. 29-Nov. 30 Entire State 15, , % 113, Sep. 04-Nov. 30 Entire State 21, , ,313 8% 196, Aug. 27-Nov. 30 Entire State 25, , ,420 7% 314, Aug. 25-Nov. 30 Entire State 26,753 1 No Survey (1,350) Aug. 24-Nov. 30 Entire State 25,863 1 No Survey (1,250) Aug. 23-Nov. 30 Entire State 25, , ,376 7% 239, Aug. 22-Nov. 30 Entire State 25, , % 202, Aug. 20-Nov. 30 Entire State 20, , % 169, Aug. 26-Nov. 30 Entire State 19, , % 202, Aug. 25-Nov. 30 Entire State 20, , % 217, Aug. 24-Nov. 30 Entire State 12, , ,172 12% 117, Aug. 29-Nov. 30 Entire State 16, , % 160, Aug. 28-Nov. 30 Entire State 17, , ,179 9% 183, Aug. 27-Nov. 30 Entire State 17, , ,250 9% 198, Aug. 26-Nov. 30 Entire State 13, , % 173, Aug. 24-Nov. 30 Entire State 22, , % 282, Aug. 30-Nov. 30 Entire State 23, , % 238, Aug. 29-Nov. 30 Entire State 27, , % 382, Aug. 28-Nov. 30 Entire State 34, , % 379, Aug. 01-Nov Entire State 37, , % 489, Aug. 01-Nov Entire State 39, , % 553,