What mice eat in the wild

General Foraging Habits

Opportunistic Eaters

Wild mice demonstrate opportunistic feeding behavior, exploiting any accessible energy source to sustain growth and reproduction. Their diet reflects immediate availability rather than strict preference, allowing rapid adaptation to fluctuating environments.

Typical food items include:

Seed kernels and grain fragments that fall from plants or storage structures.
Insect larvae, adult beetles, and other arthropods encountered during foraging.
Small amounts of carrion or dead vertebrate tissue uncovered in nests or burrows.
Fungal spores and mycelium present on decaying organic matter.
Anthropogenic waste such as discarded food scraps, crumbs, and processed residues near human habitation.

Seasonal shifts modify resource composition; early spring emphasizes emerging insects and fresh seeds, while late summer and autumn increase reliance on stored grains and fallen fruit. Opportunistic consumption reduces competition pressure, enables survival in habitats ranging from grasslands to urban perimeters, and supports population resilience despite unpredictable food supplies.

Seasonal Variations in Diet

Wild mice adjust their foraging behavior to match the fluctuating availability of resources throughout the year. During spring, seedlings, tender grasses, and newly emerged insects dominate the diet, providing protein and carbohydrates essential for rapid growth and reproduction. Summer brings an abundance of seeds from grasses and herbaceous plants, alongside increased consumption of fruits, berries, and arthropods that are most active in warm conditions. In autumn, mice prioritize high‑energy food sources such as mature seeds, nuts, and fallen fruit, storing portions for later use; fungal fruiting bodies also become a significant component as moisture levels rise. Winter forces reliance on stored reserves and low‑profile foods, including cached seeds, bark, and hardy tubers, while occasional opportunistic predation on insects trapped under snow supplies needed protein.

Spring: tender shoots, young grasses, emerging insects.
Summer: mature seeds, berries, fruit, active arthropods.
Autumn: mature seeds, nuts, fallen fruit, fungi, cache building.
Winter: cached seeds, bark, tubers, occasional trapped insects.

Primary Food Sources

Seeds and Grains

Wild mice rely heavily on seeds and grains as a primary energy source. These plant parts are abundant in grasslands, agricultural fields, and forest edges, allowing mice to sustain high metabolic rates and reproduce rapidly.

Common species consumed: wheat kernels, barley, oat groats, millet, rye, rice, and native grass seeds such as foxtail and bentgrass.
Nutrient profile: high carbohydrate content (45–65 % dry weight), moderate protein (10–15 %), low fat (<5 %); essential vitamins and minerals are present in varying amounts.
Seasonal patterns: grass‑seed availability peaks in late spring and early summer; cultivated grain residues become dominant after harvest periods, providing a reliable food influx during autumn and winter.
Foraging behavior: mice harvest seeds directly from standing stalks, collect fallen grains, and store excess in shallow caches for future use; cache retrieval accounts for up to 30 % of nightly activity in grain‑rich environments.

Preferred Seed Types

Wild mice obtain most of their caloric intake from seeds, selecting items that maximize energy return while minimizing handling effort. Preference patterns reflect seed size, nutritional density, and seasonal abundance.

Small grass seeds such as wheat, barley, and rye; easy to harvest and rich in carbohydrates.
Legume seeds including peas, beans, and alfalfa; high protein and lipid content.
Tree seeds like acorns, pine nuts, and beech nuts; provide dense fats and are stored for winter.
Weed seeds such as dandelion, thistle, and chickweed; abundant in disturbed areas and quick to collect.

Mice favor seeds with thin husks, elevated fat or protein percentages, and those that remain accessible throughout the growing season. When preferred sources decline, individuals shift to lower‑quality grains or increase foraging distance. This dietary flexibility sustains populations across diverse habitats.

Impact on Agriculture

Wild rodents primarily consume seeds, grains, sprouts, fruits, insects, and tender vegetation. Their foraging behavior concentrates on high‑energy resources that are also valuable to farmers, such as wheat kernels, corn kernels, barley, and soybeans.

Direct consumption of cultivated plants reduces yield. Field observations record loss percentages ranging from 5 % to 15 % in small‑grain crops where mouse populations exceed threshold densities. Damage includes:

Chewed kernels that become unsuitable for processing
Burrow entrances that expose soil to erosion and facilitate weed growth
Contamination of stored grain with urine, feces, and nesting material

Secondary effects amplify economic impact. By transporting seeds of invasive weeds, mice enhance competition for cultivated species. Their activity in storage facilities creates conditions for mold development, leading to further quality degradation.

Management strategies focus on habitat modification, exclusion, and population control. Exclusion methods—such as sealed storage bins and field borders—prevent entry. Population control, employing rodenticides or biological agents, reduces pressure on crops when monitoring indicates rising activity. Cost‑benefit analyses show that targeted interventions can offset losses and protect marketable output.

Fruits and Berries

Mice in natural habitats regularly include a variety of wild fruits and berries in their diet. These plant foods supply carbohydrates, vitamins, and antioxidants that support rapid metabolism and reproductive cycles.

Commonly consumed items are:

Blackberries (Rubus spp.) – abundant in late summer, high in anthocyanins.
Raspberries – soft pulp provides easy access to sugars.
Wild strawberries (Fragaria vesca) – small fruits harvested throughout spring and early summer.
Blueberries (Vaccinium spp.) – rich in vitamin C and phenolic compounds.
Mulberries – large, sweet berries that appear in late summer.
Hawthorn berries – tart fruit available in autumn, offering fiber.
Rowan (mountain ash) berries – bitter but consumed when other sources are scarce.

Mice locate these resources by scent and visual cues, often foraging near ground cover where plants produce low‑lying fruit. Seasonal fluctuations dictate reliance on fruit; during periods of scarcity, mice supplement with seeds, insects, or plant shoots. Consumption patterns reflect energy needs: high‑sugar fruits are preferred during breeding, while antioxidant‑rich berries aid in stress mitigation during harsh weather.

Availability and Consumption

Wild mice encounter a mosaic of food sources that differ markedly across habitats. Open fields supply harvested grains, fallen seeds, and weed fruits; forest floors provide fallen nuts, berries, leaf litter, and fungal sporocarps; arid regions offer grasses, seed heads, and occasional arthropods. Aquatic margins contribute insects and small crustaceans. The relative abundance of each resource fluctuates with vegetation phenology and climatic conditions.

Seasonal cycles reshape the food landscape. Spring bursts of herbaceous growth increase seed and leaf availability, prompting heightened foraging activity. Summer heat reduces seed caches, shifting intake toward insects and succulent plant parts. Autumn brings abundant nuts and fallen fruit, while winter forces reliance on stored seeds and limited arthropod prey. These temporal shifts drive adaptive changes in foraging intensity and dietary breadth.

Consumption strategies reflect high metabolic demands and unpredictable supplies. Mice exhibit:

Opportunistic sampling of any edible item encountered.
Rapid ingestion followed by immediate processing to extract nutrients.
Selective hoarding of energy‑dense seeds and nuts for later use.
Preference for protein‑rich insects when available, enhancing growth and reproduction.

Overall, the interplay between resource availability and consumption behavior enables wild mice to maintain energy balance throughout fluctuating environmental conditions.

Nutritional Value

Mice foraging in natural habitats obtain a diet composed mainly of seeds, grains, insects, and occasional plant material. This mixture supplies essential macronutrients and micronutrients required for rapid growth and high reproductive rates.

Proteins: Insect prey and seed embryos provide 12–20 % protein by weight, supporting muscle development and enzyme synthesis.
Carbohydrates: Starches and simple sugars from grains and grasses deliver 60–70 % of caloric intake, fueling constant locomotion and thermoregulation.
Lipids: Oil-rich seeds contribute 5–10 % fat, offering dense energy reserves for periods of food scarcity.
Vitamins and minerals: Wild diets contain vitamin B complex (riboflavin, niacin) from germinated seeds, vitamin E from plant oils, and minerals such as calcium, phosphorus, and zinc derived from soil‑bound plant matter and arthropod exoskeletons.

Overall caloric density ranges from 3.5 to 4.2 kcal g⁻¹, aligning with the metabolic demands of small mammals. Balanced intake of these nutrients enables mice to maintain body temperature, reproduce multiple litters annually, and sustain high activity levels despite fluctuating resource availability.

Insects and Other Invertebrates

Wild mice rely heavily on arthropods to meet protein and micronutrient requirements. Their foraging behavior targets readily encountered prey on the ground surface and within the litter layer.

Common prey items include:

Beetles (Coleoptera) such as ground beetles and weevils, which provide chitinous exoskeletons and high‑quality protein.
Crickets and grasshoppers (Orthoptera), captured during nocturnal activity when these insects are less active.
Moths and butterflies (Lepidoptera) in larval or adult form; larvae offer soft tissues that are easy to consume.
Ants and termites (Hymenoptera, Isoptera), abundant in soil and wood, supplying both protein and lipids.
Earthworms (Annelida), encountered during soil excavation, delivering moisture and amino acids.
Slugs and snails (Gastropoda), favored for their high calcium content, especially during the breeding season.

Seasonal fluctuations affect availability. Spring and early summer see a surge in insect larvae, while autumn brings an increase in beetle activity. During colder months, mice shift toward overwintering invertebrates such as dormant beetles and earthworms that remain active in the upper soil layers.

Hunting techniques are opportunistic. Mice use rapid darting motions to capture mobile prey, while employing tactile exploration with whiskers to locate hidden or immobile organisms. They often gnaw through leaf litter or soft wood to access concealed insects.

Nutritional analysis demonstrates that invertebrate consumption can supply up to 30 % of total caloric intake for wild mice, with spikes to 50 % during breeding periods when protein demand rises. Calcium from gastropods supports skeletal development, and the lipids in ants and termites provide essential fatty acids.

Overall, insects and other invertebrates constitute a vital component of the natural diet of free‑living mice, delivering essential nutrients that complement plant‑based foods.

Protein-Rich Additions

Wild mice obtain most of their protein from animal and plant sources encountered while foraging. Their small size and high metabolic rate require frequent intake of nitrogen‑rich foods to support growth, reproduction, and tissue repair.

Typical protein‑rich additions include:

Invertebrates such as beetles, moth larvae, and spiders
Earthworms and other soft‑bodied annelids
Seed kernels and nut fragments with elevated protein content
Small vertebrate remains, for example bird eggs or carrion scraps
Fungi, particularly spore‑producing fruiting bodies with moderate protein levels

Seasonal fluctuations influence availability; insects dominate in warm months, while seeds and fungi become more important during cooler periods. Consumption patterns reflect opportunistic exploitation of any high‑quality protein encountered in the environment.

Hunting Strategies

Wild mice obtain nourishment through a suite of hunting and foraging tactics that maximize energy intake while minimizing exposure to predators.

They rely on acute olfactory and auditory senses to locate seeds, insects, and small invertebrates hidden beneath leaf litter or soil. Nocturnal activity reduces competition with diurnal species and lowers predation risk; mice emerge at dusk, move swiftly along established runways, and pause to sniff for concealed prey.

Key strategies include:

Active foraging: systematic exploration of microhabitats, employing rapid, low‑profile movements to capture mobile insects such as beetles and larvae.
Seed caching: collection of grains and nuts followed by temporary storage in shallow burrows; cached items serve as a reserve during periods of scarcity.
Opportunistic predation: swift attacks on newly emerged arthropods (e.g., aphids, moth larvae) when they are most vulnerable.
Scavenging: retrieval of dead insects or plant material left by larger animals, often from the edges of predator kill sites.
Social information use: observation of conspecifics’ foraging paths, allowing individuals to exploit discovered food sources without redundant searching.

These tactics integrate sensory detection, temporal niche exploitation, and behavioral flexibility, enabling wild mice to sustain a varied diet across diverse habitats.

Green Vegetation

Wild mice rely heavily on green vegetation to meet their nutritional requirements. Leafy shoots, tender stems, and young buds provide essential carbohydrates, vitamins, and minerals that support rapid growth and high reproductive rates.

Typical plant components consumed include:

Fresh grass blades, especially species such as ryegrass and fescue
Herbaceous foliage from clover, dandelion, and plantain
Seedlings of legumes, including vetch and alfalfa
Emerging shoots of low‑lying shrubs like willow and birch

Green parts also supply moisture, reducing the need for separate water sources. Seasonal availability dictates the proportion of vegetation in the diet; during spring and early summer, herbaceous growth dominates, while later in the year mice supplement with seeds and insects as plant material declines.

Leaves and Stems

Wild mice incorporate vegetation into their diet, and foliage provides a reliable source of energy and moisture when animal prey is scarce.

Leaves are consumed opportunistically; rodents gnaw the edges to access tender tissue, then ingest the mesophyll rich in carbohydrates. Preferred leaf types include broad‑leaved herbs, young oak (Quercus spp.) foliage, and soft‑margined grasses. The high water content of fresh leaves reduces the need for separate drinking.

Stems serve both as food and as foraging material. Mice strip bark and chew young shoots to reach the cambium layer, which contains sugars and minerals. Common stem sources are reed (Phragmites), cattail (Typha), and the tender stems of thistles (Cirsium). Chewing also facilitates access to insects hidden within the plant tissue.

Nutritional contribution of foliage varies seasonally. Spring growth yields protein‑rich leaves and shoots; summer provides abundant green matter; autumn offers fibrous stems and dried leaf litter, which supply bulk and aid digestion.

Key plant groups regularly exploited:

Herbaceous dicots (e.g., dandelion, Plantago)
Young woody shoots (e.g., willow, Salix)
Aquatic emergents (e.g., bulrush, Scirpus)

Field observations confirm that foliage consumption constitutes a substantial proportion of the caloric intake for wild mice, especially in habitats where seed and insect availability fluctuates.

Roots and Tubers

Wild mice supplement their primarily seed‑based diet with a variety of underground plant parts. Roots and tubers provide carbohydrates, moisture, and minerals during periods when above‑ground food is scarce.

Commonly consumed structures include:

Carrot taproots (Daucus carota) – readily excavated in cultivated fields and open meadows.
Beet storage roots (Beta vulgaris) – attractive for their high sugar content.
Wild onion bulbs (Allium spp.) – offer both nutrients and a protective layer of skin.
Dandelion taproots (Taraxacum officinale) – abundant in disturbed habitats.
Sweet potato tubers (Ipomoea batatas) – exploited when human waste or crop remnants expose them.

Mice locate these resources by scent cues and by following soil disturbances created by other burrowing animals. Their incisors, continuously growing, enable efficient gnawing through fibrous tissue. After extraction, mice gnaw the outer skin, consume the softer interior, and discard remaining fibrous material. This behavior enhances survival in temperate and arid ecosystems where surface food fluctuates seasonally.

Less Common and Emergency Foods

Fungi and Mushrooms

Wild rodents frequently incorporate fungal material into their foraging repertoire. Seasonal availability drives consumption patterns, with peak intake during damp periods when fruiting bodies emerge.

Mushrooms provide protein, lipids, and micronutrients that complement seed and insect prey. Specific advantages include:

High‑quality amino acids supporting growth.
Essential fatty acids contributing to membrane synthesis.
B‑vitamins and trace minerals enhancing metabolic functions.

Commonly consumed taxa comprise:

Agaricaceae (e.g., field mushrooms) – soft caps, low toxicity.
Boletaceae (e.g., porcini relatives) – robust stalks, rich in carbohydrates.
Russulaceae (e.g., brittlegills) – bitter compounds that deter parasites.

Mice demonstrate selective feeding, avoiding toxic species by detecting bitter alkaloids and volatile deterrents. Consumption of non‑poisonous fungi also aids in dispersing spores, as ingested spores survive passage through the gastrointestinal tract and are deposited with feces.

Nutritional intake from fungi varies with moisture content; hydrated caps deliver up to 90 % water, reducing dehydration risk during dry spells. Energy density of dried fruiting bodies can exceed that of comparable seed kernels, providing a valuable caloric reserve.

Overall, fungal foraging constitutes a measurable component of the wild mouse diet, delivering essential nutrients and supporting survival across fluctuating environmental conditions.

Carrion

Wild mice incorporate animal carcasses into their diet when plant resources are limited or when opportunistic feeding opportunities arise. Field, wood, and house mice have been observed consuming dead insects, small vertebrates, and decomposing organic matter.

Carrion consumption increases during periods of seed scarcity, low temperatures, and after heavy precipitation. Scavenging provides a rapid source of protein, essential amino acids, and minerals such as calcium and iron, which support growth, reproduction, and immune function. The high energy density of decaying tissue can offset the energetic costs of foraging in harsh environments.

The practice carries health risks. Pathogenic bacteria (e.g., Salmonella, Clostridium) and parasitic larvae may be ingested with decomposing flesh. Mice mitigate these threats through selective feeding on fresher tissue and by limiting intake to small portions.

Ecologically, mouse scavenging accelerates carcass breakdown, redistributes nutrients, and reduces the persistence of disease vectors. Their activity complements that of larger carrion consumers, influencing decomposition rates and soil enrichment.

Species most frequently observed scavenging:
- Mus musculus (house mouse)
- Apodemus sylvaticus (wood mouse)
- Microtus ochrogaster (prairie vole)
Typical carrion types consumed:
- Insect remains
- Small mammal carcasses (e.g., dead voles)
- Bird feathers and flesh
Seasonal patterns:
- Increased intake in winter and early spring
- Reduced scavenging during summer abundance of seeds

Overall, carrion represents a supplemental, opportunistic food source that enhances the adaptive flexibility of wild mice.

Human-Related Food Waste

Wild rodents frequently exploit discarded human food, incorporating it into their natural diet. Food waste from households, markets, and agricultural processing provides high‑calorie resources that are readily accessible in many habitats.

Common categories of anthropogenic refuse consumed by mice include:

Stale bread, pastries, and cereal grains
Fruit peels, vegetable scraps, and cooked leftovers
Processed snack items such as chips, crackers, and candy
Animal by‑products like meat trimmings and fish off‑cuts
Packaged waste containing sugars, fats, and salts

The presence of such waste alters foraging behavior, increases population density, and can facilitate the spread of pathogens. Managing human food residues reduces the attractiveness of environments to wild mice and mitigates associated ecological and health impacts.

Factors Influencing Diet

Habitat and Environment

Wild mice inhabit diverse ecosystems, each shaping the range of consumable resources. Forest floors provide abundant seed banks, fallen nuts, and insect larvae uncovered by leaf litter decomposition. Open grasslands expose rodents to grasses, herbaceous seeds, and arthropods that thrive in sun‑lit soil. Arid scrublands limit vegetation, prompting reliance on hardy seeds, dried plant material, and occasional carrion left by larger predators. Wetland margins offer aquatic invertebrates, soft‑stem grasses, and floating seeds that drift into mouse foraging paths.

Key environmental factors influencing food availability include:

Seasonal plant cycles: spring germination yields fresh shoots and seeds; autumn brings mature seed drops.
Soil composition: loamy soils sustain richer invertebrate populations, while sandy substrates favor seed storage.
Predator activity: presence of raptors or snakes can drive mice to forage under cover, altering diet toward concealed ground insects.
Human disturbance: agricultural edges introduce cultivated grains and stored food waste, expanding dietary options beyond natural flora.

Understanding the interplay between habitat characteristics and resource distribution clarifies why wild mice adjust their feeding behavior according to the specific conditions of forests, fields, deserts, and wetlands.

Forest Ecosystems

Forest ecosystems provide a mosaic of plant species, seasonal fruiting cycles, and abundant invertebrate populations that shape the nutritional options for small rodents. The structural complexity of canopy, understory, and leaf litter creates microhabitats where food resources accumulate.

Typical components of a forest-dwelling mouse’s diet include:

Seeds from herbaceous and woody plants
Nuts such as acorns and hazelnuts
Fallen fruits and berries
Invertebrates: beetles, larvae, springtails
Mycelial threads and sporocarps of fungi
Bark and cambium of young saplings

Seasonal shifts alter resource availability. Spring brings a surge of insect larvae and fresh seeds; summer adds ripening berries and abundant fungi; autumn supplies mature nuts and fallen fruit; winter forces reliance on stored seeds, bark, and dormant insects.

By consuming and transporting seeds, mice facilitate plant propagation across the forest floor. Their predation on invertebrates regulates arthropod populations, influencing decomposition rates and nutrient cycling. These interactions reinforce the dynamic equilibrium of forest habitats.

Grassland Habitats

Grassland ecosystems support a diverse assemblage of small rodents whose diets reflect the seasonal availability of plant and animal resources. In these open habitats, mice exploit a range of food items that can be classified into three functional groups: seeds, vegetative matter, and invertebrates.

Seeds and grains: native grasses, wild cereals, and the seeds of forbs provide high‑energy carbohydrates.
Green vegetation: tender shoots, leaf blades, and young flower buds supplement protein intake.
Invertebrates: insects, larvae, and arachnids offer essential lipids and amino acids, especially during breeding periods.

Foraging behavior adapts to the pronounced fluctuations typical of grasslands. During spring and early summer, mice prioritize fresh shoots and insect prey, while late summer and autumn see a shift toward seed accumulation for winter storage. Water intake is largely met through moisture‑rich plant tissues, reducing the need for open water sources.

Predation pressure and competition influence diet breadth. Species that coexist in the same meadow often partition resources by selecting different seed sizes or foraging microhabitats, thereby minimizing overlap and maximizing overall energy acquisition.

Urban and Suburban Areas

Mice living in cities and surrounding residential zones exploit a diverse array of food sources that differ markedly from those found in natural ecosystems. Their foraging behavior reflects the availability of anthropogenic waste, ornamental vegetation, and fragmented green spaces.

Typical components of their urban diet include:

Grain residues from bakeries, supermarkets, and household pantries.
Fruit and vegetable scraps discarded in trash bins or compost piles.
Insects attracted to streetlights, such as beetles, moths, and larvae.
Seeds from ornamental grasses, flower beds, and roadside plantings.
Pet food left uncovered or spilled in yards.

Seasonal shifts influence reliance on specific items. In summer, abundant insect populations and fresh produce increase protein intake, while autumn sees a rise in seed consumption as ornamental plants set fruit. Winter forces mice to depend heavily on stored human food waste and the occasional rodent carrion found in sewers.

Adaptations that facilitate exploitation of these resources involve:

Enhanced nocturnal activity to avoid human disturbance.
Dexterous gnawing ability enabling access to sealed containers and packaging.
Flexible home range that incorporates both built structures and vegetated patches.

The presence of mice in urban and suburban settings creates a feedback loop with human activity: increased waste generation supports larger populations, which in turn raise the likelihood of property damage and disease transmission. Effective management therefore requires minimizing accessible food sources, securing waste containers, and maintaining vegetation that does not provide shelter or abundant seed crops.

Predation Risk and Foraging Behavior

Mice living outside human structures constantly balance the need for nutrients against the threat of predators. The presence of carnivorous birds, snakes, and small mammals forces them to modify where, when, and what they consume, shaping the overall composition of their natural diet.

Exposure to predators triggers several behavioral adjustments:

Increased vigilance: Individuals pause frequently to scan surroundings, reducing the time spent chewing and limiting intake of low‑value items.
Temporal shift: Foraging moves to crepuscular or nocturnal periods when visual hunters are less active.
Microhabitat selection: Mice choose cover‑dense patches such as leaf litter or burrow entrances, even if these areas contain fewer high‑energy seeds.

These strategies create a trade‑off between caloric gain and safety. When risk is high, mice prioritize concealed, low‑risk foods—seeds with protective husks, fallen nuts, or arthropods hidden in soil. Under reduced predation pressure, they expand to open‑ground grains and larger insects, which provide higher protein and fat but demand longer exposure.

Overall, predation risk dictates the spatial and temporal pattern of foraging, directly influencing the types of food items that constitute the diet of wild mice.

Competition with Other Species

Wild mice obtain nourishment from a variety of seeds, insects, and plant material, but the availability of these resources is constantly reshaped by interspecific competition. When other species exploit the same food patches, mice must adjust intake rates, select alternative items, or alter foraging times to maintain energy balance.

Key competitors and their influence:

Granivorous birds (e.g., sparrows, finches) deplete seed caches, reducing high‑energy kernels during breeding seasons.
Insectivorous reptiles (e.g., lizards) and amphibians consume shared arthropod prey, especially in moist microhabitats.
Sympatric rodents (e.g., voles, other mouse species) compete for underground seeds and tubers, often driving mice to peripheral foraging zones.
Small carnivores (e.g., weasels, foxes) indirectly affect diet by forcing mice to adopt more concealed foraging routes, limiting access to exposed food sources.

Mice respond with several adaptive tactics:

Broadening diet breadth to include lower‑rank items such as fallen leaves, bark, or fungal spores when preferred foods are scarce.
Shifting activity peaks to dawn or dusk, times when competitors are less active, thereby accessing residual resources.
Exploiting microhabitats (e.g., dense underbrush, burrow entrances) that provide both cover and unique food items unavailable to larger rivals.

These interactions shape the composition and seasonal variation of the wild mouse diet, ensuring survival despite persistent competition.