The Blue Grosbeak can be found throughout parts of Orange County primarily in the late spring/early summer is your best bet. A good reliable place is the Alison Woods and Canyon Park. I've reliably found this species there year after year. Continue walking past the ranger station on the main asphalt trail. They are easy to spot with their blue and brown colorful plumage and can sometimes be heard calling as well. Here are several photos from this location and also the Oso Reservoir. More from Wikipedia: The blue grosbeak (Passerina caerulea, formerly Guiraca caerulea), is a medium-sized seed-eating bird in the same family as the northern cardinal, "tropical" or New World buntings, and "cardinal-grosbeaks" or New World grosbeaks. The male blue grosbeak is a beautiful bird, being almost entirely deep blue. The female is mostly brown. Both sexes are distinguished by their large, deep bill and double wing bars. These features, as well as the grosbeak's relatively larger size, distinguish this species from the indigo bunting. Length can range from 14 to 19 cm (5.5 to 7.5 in) and wingspan is from 26 to 29 cm (10 to 11 in). Body mass is typically from 26 to 31.5 g (0.92 to 1.11 oz). This is a migratory bird, with nesting grounds across most of the southern half of the United States and much of northern Mexico, migrating south to Central America and in very small numbers to northern South America; the southernmost record comes from eastern Ecuador. It eats mostly insects, but it will also eat snails, spiders, seeds, grains, and wild fruits. The blue grosbeak forages on the ground and in shrubs and trees. With respect to its habitat, This species is found in partly open habitat with scattered trees, riparian woodland, scrub, thickets, cultivated lands, woodland edges, overgrown fields, or hedgerows. It nests in a low tree or bush or a tangle of vegetation, usually about 1–3 m (3.3–9.8 ft) above ground, often at the edge of an open area.