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Loxia curvirostra

This red crossbill is extracting seeds from ponderosa pine cones. The crossed bill helps pry open woody cone scales for removal by the tongue of seeds formed between the scales. Crossbill subspecies that feed on pines with big cones have beaks that are, on average, bigger than subspecies feeding on conifers with smaller cones like spruce and hemlock. Crossbills consume as many as 3,000 seeds per day, requiring them to wander widely each year in search of reliable pantries. 

Loxia curvirostra

This female red crossbill is pulling a western spruce budworm (Choristoneura occidentalis) from an expanding Colorado blue spruce shoot in May. Like most species with mostly vegetarian diets, red crossbills take advantage of protein-rich arthropods when available. This is particularly true when raising young, as insects and spiders are more conducive to rapid growth.

Selasphorus rufus

The rufous hummingbird is a feisty species that appears at local feeders from early July through early autumn. This female is revealing her tongue, an essential structure for feeding. It is a double tube which opens very rapidly and utilizes capillary action to pull nectar, water, and tiny arthropods from deep within flowers.

Recurvirostra americana

The American avocet uses its unique up-curved beak to deftly snap up chironomid midges from the water surface. Midge larvae are aquatic. The adults fly and resemble mosquitoes but are no threat to humans. Midge larvae and adults are important, “default” foods for many insectivorous bird species including grebes, gulls, shorebirds, and neotropical migrant songbirds.

Certhia americana

The brown creeper inches along the trunk of a spruce gleaning arthropods from the complicated substrate of tree bark. Probing and prying with its nutpick beak, it extracts insects and spiders from cracks and from underneath bark flakes. A common but seldom noticed species, it has a call that is a barely audible squeak.

Catherpes mexicanus

This canyon wren is delivering a crane fly to its nestlings. Based on the genetalia visible in this photograph, a crane fly expert was able to determine this fly is Tipula diversa.

Troglodytes aedon

This house wren has a beak-full of European earwigs (Forficula auricularia) for delivery to a cavity in an apricot tree stuffed with four clamoring nestlings. This introduced insect, considered a pest by most humans, demonstrates that even unwanted exotic species have ecological utility. The rub is that they are usually not as beneficial within food chains as native species.

Calcarius miccownii

This young McCown’s longspur found a large white-lined sphinx caterpillar and is violently shaking it into submission. This serves two purposes. Such a big morsel is easier to swallow when not moving. But even more importantly, distasteful, potentially toxic chemicals contained in the caterpillar’s gut from the plants it eats are removed.

Protonotaria citrea

The prothonotary warbler normally summers in the eastern U.S. and winters in South America. This bird is subsisting in a Colorado winter by eating European buckthorn (Rhamnus cathartica) berries. Although they can lead to unpleasant consequences, many birds make do with them in late fall-early winter. European buckthorn is an exotic invasive plant due to the spread of seeds in bird droppings.

Dendroica coronata

A male yellow-rumped warbler enjoys a miller moth (Euxoa auxiliaris) meal on the far eastern plains of southeastern Colorado. Despite the scaly packaging that includes difficult to deal with wings and legs, this moth and most of its lepidopteran relatives provide valuable energy to migrant and resident bird species alike.

Picoides pubescens

This female hairy woodpecker is delivering a large flatheaded wood borer (family Bupresidae) larva to its nestlings. These wood-boring beetles are common in conifers recently killed by fire or bark beetles. The woodpeckers chip them out from under the bark or from deep in the outer wood with their chisel-like beaks.

Sphyrapicus varius

An immature yellow-bellied sapsucker clings to a Scots pine (Pinus sylvestris) with recently pecked sap wells. Sapsuckers are a subset of woodpeckers which feed primarily on sap oozing from holes they peck in the bark of living trees. The damage they inflict does not usually injure the tree.

Lanius ludovicianus

This loggerhead shrike is perched next to a speckle-winged rangeland grasshopper (Arphia conspersa) it captured and impaled on barbed wire. Impaling is used by this predatory songbird to both attract a mate and to cache food for later consumption.

The large redshank grasshopper (Xanthippus corallipes) is typically the object most commonly impaled by loggerhead shrikes in eastern Colorado. In 2017, most of our 100 grasshopper species, including this one, were absent from the prairie. A late spring freeze might be responsible. Shrikes have options and in 2017 no reptile or amphibian, except large snakes, that moved on the prairie was safe from shrike predation.

The head of short-horned lizard impaled by loggerhead shrike. This lizard is a common prey item for shrikes. The bony heads of lizards contain little nutritional value and often remain long after the rest of the body is eaten. 

Digger bee impaled by a loggerhead shrike. While not a typical form of prey, it is illustrative of the “art of impaling” mastered by shrikes. The intent is to hold prey in a way that keeps them fresh, but most importantly keeps them. A poorly impaled object is one that dies and desiccates or one that lives but escapes. Hard insects like bees and beetles are often stuck thru the front of the head or the thorax.

Rainbow scarabs (Phanaeus vindex) are commonly in the crosshairs of loggerhead shrikes. Their bright iridescence would seem to make them the perfect object to catch the attention of prospective female mates. They are one of the many animals shrikes impale that develop in, or hide under, “cowpies”. Shrikes may somehow flush them from their humble hiding places or even flip dry ones over.