The lesser prairie-chicken (Tympanuchus pallidicinctus) is a species of prairie grouse found in the grasslands of the central and southern Great Plains of North America. Their range stretches across parts of Colorado, Kansas, New Mexico, Oklahoma, and Texas. Lesser prairie-chickens play an important role in the prairie ecosystem and have very specific habitat and dietary requirements. Understanding what lesser prairie-chickens eat is key to conservation efforts for this species.
Diet Overview
Lesser prairie-chickens are omnivores and opportunistic foragers. Their diet consists mainly of plant matter supplemented with insects and other small invertebrates. The bulk of their diet is made up of seeds, leaves, buds, flowers, and fruits of forbs and grasses. When available, corn is also readily consumed. Insects and other invertebrates become more important during spring and summer, especially for growing chicks that require extra protein. Lesser prairie-chickens obtain all needed moisture from the foods they eat.
Plant Foods
The majority of the lesser prairie-chicken diet consists of plant matter. They prefer to eat green vegetation when available but will switch to seeds and fruits as greens become more scarce in winter. Some key native plants consumed include:
Forbs
– Legumes – Partridge pea, prairie clovers, wild beans
– Composites – Engelmann daisy, black-eyed Susan, sand sagebrush
– Nightshades – Silverleaf nightshade, ground cherry
– Amaranths – Tumbleweed, pigweed
Grasses
– Little bluestem
– Sideoats grama
– Blue grama
– Buffalograss
– Sand dropseed
Shrubs
– Sand sagebrush
– Fourwing saltbrush
– Shinnery oak
In agricultural areas, lesser prairie-chickens will readily feed on wheat, milo, and introduced grasses. Corn is a favorite food when available, but it requires nearby native habitat for nesting and escape cover.
Insect Foods
While a majority of the diet is plant-based, insects and other invertebrates also contribute essential nutrients. Chicks under 5 weeks old are dependent on high protein, high energy insects to fuel their rapid growth. Even adults consume more insects during spring and summer. Types of insects eaten include:
– Grasshoppers
– Crickets
– Beetles
– Caterpillars
– Ants
– Spiders
– Snails
Seasonal Variation
The composition of lesser prairie-chicken diets shifts through the seasons as food availability changes.
Spring
Spring diet is high in green vegetation and insects, including growing forbs, new grass shoots, beetles, caterpillars, and grasshoppers. Increased protein helps recover from winter and prepares for breeding.
Summer
Summer diets still include insects to meet protein needs but shift more towards seeds and fruits as they become available. Greens, forb leaves, grass seeds, and agricultural crops are eaten.
Fall
Fall sees seeds make up most of the diet, especially as early frosts kill off tender greens. Grains like corn, milo and wheat are consumed when accessible. Some insects and greens are still taken when possible.
Winter
Food becomes scarcer in winter so lesser prairie-chickens rely on seeds of grasses and forbs buried under the snow. Browse of shrubs like sand sagebrush increases. Corn and wheat are eaten if found near cover.
Water
Lesser prairie-chickens get all their needed moisture from the foods they consume. They do not require standing water sources. Dew and metabolic water produced from food is adequate for their needs.
Habitat Requirements
Lesser prairie-chicken habitat preferences directly impact diet. They thrive in native grasslands and shrublands with a diversity of vegetation that provides food year-round. Key habitat components include:
– Mix of mid-height grasses and forbs
– Variety of native plants that produce seeds, fruits and greens
– Presence of sand sagebrush for cover
– Open landscapes with low vegetation for lekking
– Proximity to croplands like corn, wheat or milo
Loss of native prairie habitat has been the primary driver of declining lesser prairie-chicken populations. Conservation efforts focus on restoring and maintaining mixed grass prairie ecosystems. Maintaining plant diversity ensures lesser prairie-chickens have access to their required dietary components through all seasons.
Unique Physiology
Lesser prairie-chickens have some unique anatomical adaptations related to their diet. These include:
– Large crops allow them to gather and store large amounts of plant foods.
– Powerful gizzards grind up and digest coarse plant material like seeds.
– Slightly elongated and narrower beaks adapted for eating seeds.
– Shorter intestines compared to birds that eat more greens and insects.
– Feathered nostrils prevent inhalation of grass seeds when feeding.
Foraging Strategies
Lesser prairie-chickens have evolved several behavioral adaptations to locate and consume their preferred foods efficiently:
– Forage in groups to find patchy food sources – there is safety in numbers from predators.
– Follow established foraging routes between known feeding areas.
– Make seasonal shifts between breeding grounds and wintering areas to access key foods.
– Dig through snow with legs and beak to expose buried seeds.
– Frequent edges of croplands, especially cornfields which provide abundant food.
– Intentionally eat grit like sand and pebbles to assist with grinding food in gizzards.
– Chicks form crèches supervised by a few adults allowing efficient foraging.
– Males attract females by displaying at leks located in high quality habitat with abundant food.
Role in Ecosystem
As an omnivore that consumes diverse native plants and insects, the lesser prairie-chicken plays an integral role in grassland ecosystems. Positive impacts include:
– Dispersing seeds and pollinating prairie plants as they forage.
– Regulating insect populations and reducing crop pests.
– Providing food for predators like hawks and coyotes.
– Grazing that recycles nutrients back into the soil.
– Nesting and foraging activities that disturb the soil and promote plant growth.
Their key ecological role underscores the importance of conservation efforts targeting lesser prairie-chicken populations and prairie habitat preservation.
Threats to Diet
Lesser prairie-chicken numbers have declined by over 90% since European settlement of the Great Plains. This dramatic reduction is attributed to habitat loss along with impacts on their food resources. Specific threats include:
– Conversion of native prairies to cropland – eliminated diversity of native plants.
– Encroachment by trees and brush due to fire suppression – crowded out grasses and forbs.
– Overgrazing by livestock – reduced abundance and diversity of plants.
– Invasive grasses like cheatgrass that outcompete natives and have lower nutrition.
– Invasive shrubs like Russian olive that replace sand sagebrush.
– Haying during nesting that destroys eggs and kills juveniles.
– Loss of cropland food sources when agricultural practices change.
– Drought that reduces plant growth.
Conservation practices like prescribed fire, grazing management, tree thinning and native re-seeding aim to restore prairie habitat and food resources. Maintaining lesser prairie-chicken access to their required diet supports recovery of the species.
Conclusion
In summary, lesser prairie-chickens require diverse native grasslands and shrublands to provide the right mix of plant and insect foods through the entire year. Their diet consists primarily of seeds, fruits and foliage of prairie grasses, forbs and shrubs, along with protein-rich insects to fuel growth and reproduction. Conservation of existing prairie habitat and restoration of degraded grasslands is crucial to protect and expand populations of this rapidly declining grouse species. Understanding the detailed dietary preferences and needs of the lesser prairie-chicken provides guidance for effective management efforts targeting this unique bird and the prairie ecosystems they inhabit.