Spotted Grosbeak

 

Spotted Grosbeak, Pheucticus nigramaculatus L 18-20 cm, WS 32 cm, Family: Cardinalidae

 

IUCN Conservation Status: Least concern (LC)

 

Description:    

Medium-sized, stocky songbird with a large head and large, conical bill. Neck and legs short and thick. Breeding males have a black head, wings, and tail heavily marked with white, bright yellow neck, breast, and back, and white undersides. Back and flanks heavily marked with black spots, bill pale. Females mostly brown with white markings in wings and a pale supercilium. Throat and breast have a slight yellowish wash, flanks have limited, subtle spotting. Juveniles appear similar to females, though immature males may show more vibrant yellow on throat and breast. Males may be confused for Merriam's Goldfinch, but much larger.   

Voice:

Song is a melodious series of clear, sweet, whistled notes that rises and falls in pitch, usually lasting 5 seconds. Sounds similar to the song of the Halley’s Robin, but more musical and slurred. Both sexes sing. Calls include a quick, sharp chip and hoarse rasping when alarmed.  

Range and Habitat:    

Breeding range encompasses the entirety of Novasola but migrates away from the interior prairie for the winter months. They prefer mosaic landscapes of diverse vegetation communities like forest/meadow patches or forest edges. Areas that provide large trees, open areas, complex understories, and close access to bodies of water are best, like riparian areas with dense streamside vegetation, forested wetlands, and alpine meadows. They avoid large areas of monotonous biome like dense forest or open grassland, especially in the winter. They are also common in suburban landscapes and are frequently seen in parks, orchards, and at backyard feeders. Some populations migrate off-island to winter in Oregon and California.

Discussion:      

Spotted Grosbeaks are most often seen in edge ecosystems, which generally means places where two distinct biomes, landscapes, or vegetation communities meet. This is most obvious where forests meet meadows or clearings, and edges are especially prevalent in areas of high disturbance, habitat fragmentation, development, or abrupt changes in elevation or precipitation. Thus, grosbeaks are common in suburbs and human-dominated landscapes where they are easily observed. As a result, Spotted Grosbeaks are well-known and well-studied among Novasolan endemics. They have also suffered less drastic population declines than most endemic songbirds and have actually seen an expansion of habitat across their range.

Spotted Grosbeaks have a varied diet of invertebrates and plant material. During the summer grosbeaks will predominantly eat insects and other invertebrates, as well as fruits. Though they glean most of their prey, they will occasionally snatch prey from mid-air. During the fall they change their diets to almost entirely fruits like berries, and in the winter they will eat other vegetation, especially seeds and buds. At birdfeeders grosbeaks prefer sunflower seeds, mealworms, suet, and fruit. The grosbeak’s namesake heavy bill helps in cracking large seeds or hard-bodied insects.

During the breeding season, both male and female Spotted Grosbeaks sing. Males sing to establish territories and attract females, and it seems female songs serve to strengthen pair bonds and their claims on a territory. Once paired, they are fiercely monogamous, but they may find new mates from year to year. Males will defend the territory from other males, while females will ward off other females from approaching the nest or the paired male. Both sexes aid equally in building the nest, incubating eggs, and rearing young. After the offspring have fledged, they may stay with the parents for the duration of that first summer. Outside the breeding season grosbeaks are fairly independent and are rarely seen in groups, especially ones greater than three or four individuals.

Unlike its close relatives, the Spotted Grosbeak does not generally make long-distance migrations. Other members of the genus Pheucticus, like the Black-headed and Rose-breasted Grosbeaks, migrate to Central or South America for the winter, as will other members of the Cardinalidae family like the Violet Bunting or Novasola Tanager. Spotted Grosbeaks, however, remain on Novasola year-round, and many individuals remain in within a hundred kilometers of their breeding territory. Other individuals, like those that breed in the prairie, are short-distance migrants which spend the winters in more forested areas near the coasts. A small number of Spotted Grosbeaks migrate off island each year, but few travel farther south than northern California. Because only some birds migrate, the Spotted Grosbeak can be considered a partial migrant.    

 

Spotted Grosbeaks are common across Novasola, and fairly recognizable in both appearance and sound. Because of their association with man-made habitats like orchards, parks, and hedgerows, they were already well-documented by the time of the NRC expeditions. Richard Reichwald encountered many during the expeditions, and afterwards found multiple grosbeak nests around Cape George.  

 

“This morning I felt for the first time assured in my familiarity with the chorus of birdsong. As with each dawn I was struck by the richness of the choir, not just in numbers but it the diversity of species, but on this morning I confident that no mysteries sang among them. In these parts at the very least, I know now the songs of the thrushes, the warblers, the sparrows. I recognize the calls of the jays, the drumming of the woodpeckers. I can mark my progress with this skill in my familiarity with the Grosbeak. No doubt a younger me, by even one month, would not notice the subtle differences between the Grosbeak song and that of the Comet Thrush. So similar are they that without devoting one’s entire attentions he would fail to distinguish them. Much like two conductors with the same piece, the real differences lie in tempo, attitude, and instrumentation, as it were. The Grosbeak’s song is effortlessly more musical, so sweet and clear and even-tempoed to the slow, slurry thrush song.” – Expedition log, April 20th, 1903

 

“The Spotted Grosbeak is in many ways similar to the Black-headed Grosbeak of western America, though more handsome. The Novasolan bird’s brilliant yellow nape and breast contrast with the clean black and white markings which altogether outshines its relative. Females share not in this fashion and may be easily mistaken for a finch or sparrow.” – Manual to Novasolan Birds, 1914

 

“Spotted Grosbeaks are noble in their partnerships, with both males and females sharing all the duties of keeping the home. While this is a beautiful matrimony, it is perhaps no less than necessary for each to share in the duties of nest building. Skilled in this labor they are not. Grosbeaks insist on building a nest bowl from twigs and grasses, much in the likeness of other tree-nesting birds, but with impatience or hurry. Grosbeak nests are so poorly constructed that I have on multiple occasions been able to see the eggs within just by looking upwards through the bottom of the nest itself. These nests are weakly held together, filled with large holes and gaps, and are insecurely attached to the tree. While adults fiercely defend their progeny from carnivorous intruders, they can do little to protect them from gravity or gale, and I have no doubt that a large portion of Grosbeak mortality must be attributed to juvenile death at the hands of an unraveled home.” – Native Birds of Novasola, 1912