Ask most people what brown bears eat and you will get the same short answer: salmon and meat. That answer is almost entirely wrong. Across nearly the entire global range of Ursus arctos, brown bears eat more grass than venison, more berries than fish, and more roots than ribs. The iconic bear standing in a waterfall snatching a sockeye is real, but it represents a tiny minority of bear populations feeding for a few short weeks a year. The rest of the time, and nearly everywhere else, the brown bear is a slow, patient, plant-focused omnivore with a digestive system built for forage rather than for flesh.
This guide walks through the full brown bear diet in the detail the subject deserves: the seasonal cycle, the regional contrasts between coastal Alaska, Eurasia, and the Mediterranean, the hyperphagia phase that lets bears survive seven-month hibernations, the salmon ecosystems that a handful of populations engineer, and the uncomfortable truth about garbage. By the end you will understand why a 600 kg Kodiak and a 90 kg marsican bear, both members of the same species, make completely different food choices every day of the year.
The Short Answer: Opportunistic Omnivores, Mostly Plants
Brown bears are opportunistic omnivores. That is not a hedge. It is the defining statement of their feeding biology. Every dietary fact about the species flows from it.
Opportunistic means the bear eats whatever is abundant, accessible, and calorie-dense at that moment of the year in that specific location. Omnivore means its gut, dentition, and metabolism can handle both plant and animal material. Put those two traits together and you get an animal that in June eats fresh grasses on an alpine meadow, in July digs glacier lily bulbs, in August strips blueberry bushes for twelve hours a day, in September chases salmon or splits open a dead moose, and in October hauls acorns from under beech and oak canopies. Each population specialises to its landscape; none specialises away from the plant-heavy default.
The headline numbers most ecologists cite:
- Eurasian brown bears: 85 to 95 percent plant matter by volume in most regions
- Interior North American grizzlies: 70 to 90 percent plant matter annually
- Coastal Alaskan and Kamchatka bears: up to 80 percent salmon between August and October; plants still dominate the remaining nine months
- Mediterranean bears (marsican, Cantabrian, Pyrenean): above 90 percent plant matter, animal protein almost entirely from insects and carrion
Even in the "bears eat salmon" populations that drive the popular image, annual dietary composition across a full calendar year remains plant-dominated. Salmon is a brief gorge, not a lifestyle.
"People think of bears as carnivores because they have the teeth of carnivores and the ancestry of carnivores. But if you watch what they actually eat, they spend the overwhelming majority of their waking hours chewing plants. That mismatch between the face of a predator and the habits of a grazer is one of the most fascinating things about the genus."
- Charlie Robbins, Washington State University Bear Center
Brown Bear Diet by Region
No single description of "the brown bear diet" holds across the species. The best way to see the range is side by side. The table below summarises what researchers have found in the major brown bear populations of the world, drawn from scat analysis, stable isotope studies, and direct observation.
| Region | Primary plant foods | Primary animal foods | Approx. plant share |
|---|---|---|---|
| Scandinavia (Sweden, Norway, Finland) | Bilberry, crowberry, cowberry, grasses, ants | Moose calves (spring), scavenged carrion | 85-90% |
| Carpathians (Romania, Slovakia) | Beechnut, acorn, raspberry, hazelnut, apples, plums, maize | Wild boar piglets, roe deer, livestock, carrion | 80-90% |
| Cantabrian Spain | Chestnut, acorn, bilberry, apples, honey | Carrion, insects, occasional livestock | 90-95% |
| Italian Apennines (marsican) | Apennine buckthorn, cherry, apple, plum, corn | Insects, rare carrion | 95%+ |
| Interior Alaska / Yukon | Soapberry, blueberry, horsetail, glacier lily | Moose calves, ground squirrels, salmon (where accessible) | 70-85% |
| Coastal Alaska (Katmai, Kodiak) | Sedges, grasses, berries in summer | Salmon (Aug-Oct), clams, marine carrion | 40-60% annually |
| Kamchatka Peninsula | Pine nuts, grasses, berries | Salmon, marine mammals (rare), rodents | 50-70% annually |
| Hokkaido (Japan) | Oak acorns, bamboo grass, Sasa, walnuts | Salmon, sika deer, carrion | 75-85% |
| Himalaya / Tibetan Plateau | Alpine grasses, sedges, roots, pikas | Pikas, marmots, livestock (rare) | 80-90% |
| Gobi Desert (Mongolia) | Wild rhubarb, wild onion, ephedra, nitraria | Virtually none | 95%+ |
Two patterns jump out. First, the plant-heavy default is nearly universal. Even the most carnivorous populations on Earth eat more plants than meat when you count across the whole year. Second, the specific plants matter enormously. Beechnut masting years in central Europe can double a bear's pre-hibernation fat reserves. Bilberry failures in Scandinavia push bears toward livestock and human areas. A salmon run collapse in Kamchatka sends bears into ungulate ranges they would otherwise ignore. The bear is generalist; the food supply is not.
For a deeper look at the geographic backdrop behind these diet patterns, see the companion guides on brown bear subspecies and where European brown bears live.
The Seasonal Cycle
Brown bear feeding is not continuous. It moves through a sharply seasonal rhythm built around the availability of green vegetation in spring, berry and nut masting in late summer and autumn, and the fasting months of winter hibernation. Every wild bear in a temperate or subarctic climate follows roughly the same annual calendar, with local variations for salmon, masting trees, or ungulate calving peaks.
| Season | Dominant foods | Main feeding behaviour | Daily calorie target |
|---|---|---|---|
| Late winter / early spring | Carrion from winter kills, overwintered berries, emerging grasses | Slow, scavenging, testing the landscape | 4,000-8,000 kcal |
| Spring (April-June) | Fresh grasses, sedges, ungulate calves, horsetail, skunk cabbage | Grazing, calf hunting, scat mostly green | 6,000-12,000 kcal |
| Summer (June-August) | Berries, insects, fish, small mammals, ungulates | Continuous foraging, long active hours | 10,000-15,000 kcal |
| Late summer (August-September) | Ripening berries, salmon runs, pine seeds | Peak feeding begins, fat deposition starts | 15,000-20,000 kcal |
| Autumn (September-November) | Acorns, beechnuts, chestnuts, salmon, ungulate kills | Hyperphagia, near-continuous feeding | 20,000+ kcal |
| Winter (November-April) | None (hibernation) | Fasting, metabolic slowdown | 0 kcal intake |
The transition from feeding to hyperphagia is the single most dramatic shift in brown bear behaviour. In hyperphagia a bear may feed for 20 hours out of 24 and gain roughly one kilogram of body mass per day for six to twelve consecutive weeks. The animal becomes a fat-deposition machine. Hormonal changes tied to day length and ambient temperature shift its metabolism toward storage, and its food selection tightens onto whichever calorie source is densest in that specific landscape. Understanding this cycle is the prerequisite for understanding brown bear hibernation, which is essentially the other half of the annual energy equation.
"The bear does not decide to hibernate. The bear decides to fatten, and hibernation is what happens when the fattening succeeds. A bear that fails to enter hyperphagia fails to breed, and in bad mast years a female may skip pregnancy entirely. Food, not weather, sets the clock."
- Djuro Huber, University of Zagreb, lead researcher on Dinaric brown bears
Plant Foods in Detail
Berries
Berries are the single most important food category for brown bears across most of their range. The reasons are straightforward: berries are sugar-rich, widely distributed, and available in predictable late-summer pulses that align perfectly with the onset of hyperphagia.
The key species vary by continent but the list is remarkably consistent:
- Bilberry (Vaccinium myrtillus) - European mainstay, dominant in Scandinavian and Carpathian diets
- Lingonberry / cowberry (Vaccinium vitis-idaea) - Northern forests, overwinters and feeds bears in early spring
- Buffaloberry (Shepherdia canadensis) - North American interior, up to 200,000 berries eaten per bear per day
- Blueberry (Vaccinium spp.) - Widespread, the iconic grizzly berry of the Pacific Northwest
- Raspberry, thimbleberry, salmonberry - Mixed forest and edge habitat
- Crowberry (Empetrum nigrum) - Tundra and high latitudes
- Cranberry, huckleberry, elderberry - Regional components
- Apennine buckthorn (Rhamnus alpina) - Critical for the Italian marsican bear
The buffaloberry figure above is not a typo. Detailed studies of grizzly foraging in Alberta and Montana have documented individual bears consuming more than 200,000 berries in a single day during peak ripening. A bear picks by raking the fruit-laden branch through its lips with the tongue and teeth, swallowing the berries whole and excreting the intact seeds kilometres away. Seed dispersal is one of the major ecological services brown bears provide in every forest they occupy.
Nuts, Seeds, and Mast
Where berries fuel summer, mast (the nuts and seeds of forest trees) fuels autumn. Mast is extraordinarily fat-dense and calorie-dense, often two to five times the energy per gram of fresh berries, and it is the single most important pre-hibernation food for forest-dwelling populations.
Key mast crops by region:
- Beechnut (Fagus sylvatica) - Carpathians, Balkans, Cantabrian Spain; masting years drive bear reproductive success
- Acorn (Quercus spp.) - Oak forests of Europe and North America, a dietary keystone for Cantabrian and Iberian bears
- Hazelnut (Corylus avellana) - Northern and central Europe
- Chestnut (Castanea sativa) - Mediterranean Europe, increasingly important where beech fails
- Whitebark pine seeds (Pinus albicaulis) - Greater Yellowstone and northern Rockies, a historically critical food now threatened by blister rust
- Korean pine seeds (Pinus koraiensis) - Russian Far East, Ussuri bears
- Siberian pine seeds - Kamchatka, inland Russia
The dependence on mast is why climate-linked mast failures are one of the most serious indirect threats to brown bear populations. When the beech crop fails in the Carpathians, bears enter hyperphagia without a fat bank to draw on, descend to low elevations, raid orchards and rubbish dumps, and show up in human villages. The resulting spike in conflict killings is a mast failure in disguise.
Roots, Tubers, and Bulbs
In terrain where berries and nuts are scarce - alpine meadows, tundra, subarctic grasslands - brown bears survive by digging. The shoulder hump that defines the species is pure digging muscle, and the front claws that can reach 10 cm in grizzlies are digging tools before they are weapons.
Dietary staples from the soil include:
- Glacier lily (Erythronium grandiflorum) bulbs - alpine North America, dug in spring as snow recedes
- Sweetvetch (Hedysarum spp.) roots - taproots dug on talus slopes and river flats, a staple of northern interior grizzlies
- Yampa, biscuitroot, spring beauty - corms and tubers
- Pignut, earthnut, wild onion - European meadow bears
- Rhubarb and onion species - Gobi and Himalayan bears
- Skunk cabbage rhizomes - Pacific Northwest coastal populations
A single bear excavating a sweetvetch bank can turn over several cubic metres of soil in a morning. The effect on alpine and subalpine meadows is significant enough that ecologists classify brown bears as ecosystem engineers in their digging role, comparable to the engineering role of beavers and elephants in their own habitats.
Grasses, Sedges, and Forbs
The least glamorous but often largest category by volume is green forage: young grasses, sedges, and broad-leaved forbs consumed in spring and early summer when they are still tender and protein-rich. Sedge meadows along Alaskan coasts support dense bear populations long before any salmon arrive, and European meadow complexes are critical spring foraging zones. The classic image of a coastal grizzly "grazing" on a sedge flat with its head down like a cow is not a rare scene. It is how most coastal bears spend most of their summer daylight hours.
Animal Foods: What Brown Bears Actually Hunt and Scavenge
Despite the plant-heavy reality, brown bears are genuine predators when opportunity allows. The key is that opportunity is rare and unpredictable for a 300 kg animal that is fast for its size but still slower and clumsier than its prey. Most large mammal predation is opportunistic, most scavenging is routine, and insects are the unglamorous workhorse of the animal side of the diet.
Ungulate Predation
Brown bears take:
- Moose calves (North America, Scandinavia) - peak predation in May and June, during the first six weeks of calf life
- Elk calves (North American Rockies) - concentrated during the calving pulse in late May and early June
- Reindeer and caribou calves (Scandinavia, Russia, Alaska) - where ranges overlap
- Roe deer and red deer calves (Europe) - opportunistic
- Wild boar (Europe, Russia) - mostly piglets, occasionally larger animals
- Livestock (sheep, goats, cattle) - in areas with unguarded pastoralism
Predation on adult ungulates is rare but not nonexistent. Adult moose killed by brown bears have been documented in Scandinavia, Alaska, and the Russian Far East, usually in deep snow or ambush situations where the prey's mobility is limited. The bear typically pins and bites the neck or skull. Once down, a moose represents weeks of food if the bear can defend the carcass from wolves, eagles, and other bears.
Carrion Scavenging
Carrion is a year-round food for every brown bear population studied. Bears locate carcasses by scent from kilometres away and routinely displace wolves, wolverines, and smaller carnivores from their kills. In early spring, carrion from winter-killed ungulates is often the first substantial food a bear encounters after emerging from the den, and in some northern populations spring carrion intake rivals later summer feeding in calorie terms.
Insects
Insects look trivial until you count calories. They are not trivial. Insect consumption is a major part of the brown bear diet in most populations and the dominant animal protein source in several.
- Ants (Formica, Camponotus) - bears tear apart rotting logs and anthills, eating adults, pupae, and eggs
- Bee and wasp larvae - raided from ground nests and tree hives, often with no regard for stings
- Yellowjackets - similar
- Army cutworm moths - aggregate on high-elevation talus in the northern Rockies; grizzlies climb to 3,000+ metres to eat them by the tens of thousands
The moth aggregations are the most striking case. Grizzlies in the Greater Yellowstone ecosystem routinely climb to rocky talus slopes above treeline in July and August to flip rocks and lap up army cutworm moths, which are over 50 percent fat by dry weight. A single bear can consume 40,000 moths in a day, absorbing roughly 20,000 kilocalories of pure fat without ever touching a large animal.
Salmon
And then there is salmon, the food that made the brown bear famous.
Salmon: The Great Gorge
Between late July and late October in a small number of coastal watersheds, brown bears behave almost nothing like brown bears anywhere else. Dozens of adults gather at a single waterfall or stream confluence. Hierarchies tighten. Hunting sequences are learned from mothers. The plant-heavy generalist becomes, briefly, one of the most specialised fish predators in the temperate zone.
The major salmon-gorging populations are:
- Coastal Alaska (Katmai, Kodiak, Admiralty, Kenai) - sockeye, pink, chum, coho
- Kamchatka Peninsula (Russia) - the largest salmon-dependent bear population on Earth, estimated at 10,000-15,000 bears
- British Columbia coast - Great Bear Rainforest populations
- Hokkaido - Ussuri brown bears exploiting masu and chum runs
- Sakhalin Island - Russian Far East
At prime fishing locations the spectacle is extraordinary. The McNeil River State Game Sanctuary in Alaska concentrates up to 75 bears at a single falls during the chum run, the highest documented aggregation of brown bears anywhere. Brooks Falls in Katmai National Park regularly hosts 25-40 bears visible in frame at once. The density is only possible because salmon is so calorie-rich that defending personal foraging territory becomes less worthwhile than tolerating neighbours.
Intake during peak runs is staggering. An adult male can land and consume 30 to 40 kilograms of salmon per day under normal conditions, with exceptional individuals at peak fishing spots eating the caloric equivalent of 60 to 80 kilograms when runs are thick. Bears practise selective consumption: when salmon are abundant they strip only the fattiest tissues (brain, skin, roe in gravid females) and discard the rest. A half-eaten salmon carcass on the bank is not waste. It is the main delivery mechanism of marine-derived nitrogen into the surrounding forest.
"In Kamchatka the bears are basically moving the ocean into the forest. Every salmon they leave half-eaten on the bank becomes a nitrogen injection into the riparian soil. Fifteen to twenty-five percent of the nitrogen in the old-growth spruces along some of these rivers originated in the Pacific Ocean and arrived there in the jaws of a bear."
- Sergey Pazhetnov, Russian bear biologist
This ecosystem-engineering role is one of the reasons salmon conservation and brown bear conservation are linked in coastal management plans. Lose the salmon and you do not just lose the bears; you lose the nutrient flux that built the forest.
Details on how grizzly populations specifically exploit these runs are covered in the companion guide on what grizzly bears eat. The contrast with the ice-bound hunting strategy of polar bears, whose diet focuses almost entirely on ringed and bearded seals, is one of the sharpest dietary divergences among closely related carnivores.
Optimal Foraging: The 17% Protein Finding
One of the most surprising findings in bear nutritional biology comes from controlled feeding experiments at the Washington State University Bear Center. When captive brown bears are given an unlimited buffet of salmon, beef, and carbohydrate-rich fruits and allowed to select their own ratio, they do not maximise protein. They converge on a diet of roughly 17 percent protein by metabolisable energy, making up the remaining 83 percent from fats and carbohydrates.
This finding rewrote a lot of assumptions. Earlier thinking treated brown bears as protein-limited carnivores that would eat meat whenever possible. The actual preference is for the mix that maximises fat deposition, and that mix is strongly skewed toward sugar and fat rather than protein. Salmon, which is about 23 percent protein and 10-15 percent fat, is therefore ideal in combination with berries and nuts but suboptimal as a sole food. Coastal bears that gorge on salmon without available plant material actually grow less efficiently than bears that alternate between salmon and berry patches.
"Bears select for the macronutrient mix that maximises fat deposition, not for maximum protein. When they have the choice they take about 17 percent protein and fill the rest with fats and carbs. That means a berry patch next to a salmon stream is more valuable than either one alone, and it explains why the best bear habitat in the world is a mosaic, not a single resource."
- Charlie Robbins and colleagues, Journal of Animal Ecology, 2014
The practical consequences are significant. Bear habitat management in Alaska, British Columbia, and Kamchatka increasingly focuses on preserving the full mosaic of coastal sedge meadows, salmon streams, and berry patches rather than any single element. Losing the berries hurts the bears even if the salmon are intact.
Hyperphagia: The 20,000 Kilocalorie Day
Hyperphagia is the window in which a year of feeding becomes a winter of fasting. It runs from late August to den entry in October or November, depending on latitude, and transforms the bear's feeding behaviour in measurable ways.
Physiological signatures of hyperphagia include:
- Feeding hours extend to 20+ out of 24
- Daily energy intake climbs from roughly 10,000-15,000 kcal in summer to 20,000+ kcal in late autumn
- Body mass gain of approximately one kilogram per day for six to twelve weeks
- Fat fraction rises from 15-20 percent to 30-40 percent of body mass
- Blood lipid levels, insulin sensitivity, and cortisol all shift toward storage
- Aggression over food patches increases, particularly in males
A large Kodiak male entering hyperphagia at 450 kg may exit it at 550-600 kg, with almost all of the added mass stored as subcutaneous and abdominal fat. That fat is the bear's fuel, water supply, and protein reserve for the five to seven months of hibernation ahead. In the companion guide on how big brown bears get, the staggering range of body sizes across the species is explored in detail; hyperphagia is one of the main proximate drivers of that variation.
"A female brown bear who does not lay down sufficient fat will simply not implant the embryos. She ovulated in June. The fertilised eggs have been floating in her uterus for months. If she reaches October below threshold body condition, they never implant and she does not give birth. Food determines the next generation directly."
- Andrew Hirschfeld, bear biologist
This mechanism, known as delayed implantation, is one of the most consequential links between diet and demography in any large mammal. A bad mast year in the Carpathians or a failed salmon run in Kamchatka produces not only thinner bears but also a smaller cohort of cubs the following spring.
Garbage, Orchards, and the Habituation Problem
Brown bears are intelligent, long-lived, and adaptable. Those traits make them outstanding opportunists, and unfortunately they also make them outstanding users of human food sources when those become available.
Anthropogenic food sources in brown bear diets include:
- Orchards (apples, plums, pears) in Romania, Slovakia, Italy, Japan
- Maize and sunflower crops in eastern Europe
- Unsecured livestock feed and silage
- Beehives (a long-running conflict in the Pyrenees, Balkans, and Hokkaido)
- Rubbish dumps and landfill sites
- Campground food and improperly stored hiker supplies
- Salmon hatcheries (Alaska, Russia)
- Bird feeders and chicken coops
A bear that learns to associate humans with food is a bear on a short timeline. Habituation leads to closer approaches, closer approaches lead to incidents, and incidents overwhelmingly end in the bear being killed. This is one of the core reasons the question of bear danger to humans is so tightly bound to food management. The bears that kill people are not usually natural predators. They are usually food-conditioned animals that have lost the normal avoidance response.
Well-managed landscapes use bear-resistant bins, electric fencing around orchards and beehives, prompt carcass removal at livestock operations, and strict food storage rules at campsites. Where those measures are in place, brown bear populations can coexist with high human densities, as they do across much of Romania and parts of Scandinavia. Where they are absent, the bears become problem bears, and problem bears become dead bears.
Cubs, Mothers, and Milk
For the first several months of life, a brown bear's diet is its mother's milk. Cubs are born in midwinter inside the hibernation den weighing 340-680 grams, and they nurse on rich, high-fat milk (around 33 percent fat, among the richest mammalian milk outside the pinnipeds) through the remainder of hibernation. By the time the family emerges in April or May the cubs weigh 5-8 kg and are ready to begin sampling solid food.
Solid food introduction follows the seasonal calendar. Cubs watch and copy. They try the grasses the mother grazes, the berries she rakes, the carcasses she opens. By their first autumn they are eating nearly the full adult diet, still supplemented by nursing that may continue through the second or even third summer in slower-growing populations. Much of what a bear knows about food - which berry patches produce reliably, which streams hold salmon, which carcasses to approach and which to avoid - is learned behaviour passed from mother to cub across two to three shared summers. A mother bear without a reliable personal food map produces cubs without one.
This maternal transmission of diet knowledge is one of the reasons brown bear populations recover slowly after crashes. Killing an experienced female kills an entire food database.
Why the Myth Persists
If brown bears are 80 percent plant eaters, why does the salmon-snatching predator image dominate public perception so completely? Three reasons.
First, visibility bias. A bear grazing on a sedge flat is boring footage. A bear catching a sockeye mid-air is iconic footage. Every nature documentary in the last 70 years has leaned on the salmon scene because it is what film cameras and tourist viewing platforms are built to capture. The weeks of silent berry-stripping and root-digging never make the cut.
Second, cultural inheritance. Bears in European folklore are predators. Bears in indigenous North American traditions are often hunters and spirit-warriors. Bears in modern children's books eat honey and fish. Almost no cultural tradition describes bears as berry-grazers or root-diggers, even though that is what they spend most of their lives doing.
Third, biological confusion. Bears have the dentition, claws, and body plan of carnivores. The order Carnivora is a taxonomic label, not a dietary description, but the visual association between "big teeth and claws" and "eats meat" is irresistible. Giant pandas are also in Carnivora and eat almost exclusively bamboo. Brown bears are less extreme, but they are closer to giant pandas in feeding ecology than most people realise.
The corrective view is simple. A brown bear is an enormous, powerful, omnivorous grazer that occasionally catches fish, very occasionally kills a calf, and constantly eats plants. That is the animal. Everything else is exception.
Tools and Further Reading
Curious readers looking to test their own understanding of animal biology may enjoy the science-focused puzzles at whats-your-iq.com. Writers and educators covering natural history topics can find useful templates and style guides at evolang.info. For technical readers working with photo essays, maps, or field data, the file conversion tools at file-converter-free.com handle most formats encountered in wildlife documentation.
The Numbers at a Glance
- Brown bears are opportunistic omnivores, not predators. Across their global range 70 to 95 percent of the annual diet by volume is plant matter.
- The plant foods that matter most are berries (bilberry, buffaloberry, blueberry, lingonberry), nuts and mast (beechnut, acorn, hazelnut, whitebark pine), roots and bulbs (glacier lily, sweetvetch), and green forage (grasses, sedges, horsetail).
- Animal foods include insects (ants, bee larvae, army cutworm moths), ungulate calves (moose, elk, roe deer), carrion year-round, and salmon in the small minority of populations with access to spawning runs.
- Coastal populations in Alaska, Kamchatka, British Columbia, and Hokkaido gorge on salmon during August-October peaks but still eat plants for most of the year. Eurasian and Mediterranean populations depend heavily on beechnut, acorn, chestnut, and regional berries.
- Hyperphagia before hibernation drives daily intake above 20,000 kcal and daily weight gain of roughly 1 kg. Failed mast or salmon years translate directly into failed pregnancies through delayed implantation.
- Controlled experiments at the WSU Bear Center show brown bears prefer a diet of about 17 percent protein, selecting for fat deposition rather than maximum protein intake.
- Salmon-feeding bears in Kamchatka and coastal Alaska act as ecosystem engineers, transferring marine-derived nitrogen into riparian forests at scales that shape old-growth nutrient cycles.
- Brown bears that access human food sources become habituated and eventually dangerous. Food storage, electric fencing, and secured waste are the single most effective conservation tools.
For the full species overview see the main brown bear entry. For context on related species, see the companion guides on grizzly bear diet, polar bear diet, and European brown bear range.
References
- Robbins, C. T., Fortin, J. K., Rode, K. D., Farley, S. D., Shipley, L. A., and Felicetti, L. A. (2007). Optimizing protein intake as a foraging strategy to maximize mass gain in an omnivore. Oikos, 116(10), 1675-1682. https://doi.org/10.1111/j.0030-1299.2007.16140.x
- Erlenbach, J. A., Rode, K. D., Raubenheimer, D., and Robbins, C. T. (2014). Macronutrient optimization and energy maximization determine diets of brown bears. Journal of Mammalogy, 95(1), 160-168. https://doi.org/10.1644/13-MAMM-A-161
- Bojarska, K., and Selva, N. (2012). Spatial patterns in brown bear Ursus arctos diet: the role of geographical and environmental factors. Mammal Review, 42(2), 120-143. https://doi.org/10.1111/j.1365-2907.2011.00192.x
- Hilderbrand, G. V., Schwartz, C. C., Robbins, C. T., Jacoby, M. E., Hanley, T. A., Arthur, S. M., and Servheen, C. (1999). The importance of meat, particularly salmon, to body size, population productivity, and conservation of North American brown bears. Canadian Journal of Zoology, 77(1), 132-138. https://doi.org/10.1139/z98-195
- Stenset, N. E., Lutnaes, P. N., Bjarnason, V., et al. (2016). Seasonal and annual variation in the diet of brown bears Ursus arctos in the boreal forest of southcentral Sweden. Wildlife Biology, 22(3), 107-116. https://doi.org/10.2981/wlb.00194
- Mattson, D. J., Gillin, C. M., Benson, S. A., and Knight, R. R. (1991). Bear feeding activity at alpine insect aggregation sites in the Yellowstone ecosystem. Canadian Journal of Zoology, 69(10), 2430-2435. https://doi.org/10.1139/z91-341
- Helfield, J. M., and Naiman, R. J. (2006). Keystone interactions: salmon and bear in riparian forests of Alaska. Ecosystems, 9(2), 167-180. https://doi.org/10.1007/s10021-004-0063-5
- Ciucci, P., Tosoni, E., Di Domenico, G., Quattrociocchi, F., and Boitani, L. (2014). Seasonal and annual variation in the food habits of Apennine brown bears, central Italy. Journal of Mammalogy, 95(3), 572-586. https://doi.org/10.1644/13-MAMM-A-218