Referring to the Isle of Pines, W. E. C. Todd (1916) writes: “This is a bird of the mangroves, to which it is apparently exclusively confined. It is accordingly most numerous along the coast and about the islands of Siguanea Bay, where the mangroves are so constant and pronounced a feature. Mr. Read has observed it along the Pine River also, but it is apparently a rare bird in the northern part of the island, judging from the dearth of records, and, indeed, it cannot be called a common bird in any locality as yet visited. Two nests were found, both in mangroves within a few feet of the water, during the third week in April, but as yet without eggs.”
More recently, this warbler has been found breeding on some of the lower Florida Keys. Earle R. Greene (1942) writes:
While exploring one of the Bay Keys in the Great White Heron National Wildlife Refuge off Key West, Florida, on June 15, 1941, with Roger Tory Peterson of the National Audubon Society, a male warbler, in full song, was located. * * * On June 26, the writer located it again on the same key, and on the 28th the male, female and nest were found. The last was in the top part of a red-mangrove tree (Rhizophora mangle) and was composed of seaweed and feathers; it contained one egg, white with brownish markings chiefly about the larger end. On July 10, the egg was found broken, apparently jabbed, possibly by a Red-wing nesting nearby. On July 16, the male bird was collected, and on the 30th the female.
Later (1944) he says: “Since then, a male and female were seen on June 16, 1942, on these same keys, and on July 14, 1942, an adult female was noted on the same keys. On August 6, 1942, a male and female, as well as an immature bird, being fed by an adult, were found on Big Mullet Key in the Key West Refuge, which is several miles from the Bay Keys. A letter received from Mrs. Frances Hames states that she found one bird, in song, on one of the Bay Keys on May 30, 1943. I consider it, therefore, a regular nester on certain keys in that area. Additional investigations may determine it as a common breeder.”
DENDROICA PETECHIA CASTANEICEPS Ridgway
MANGROVE YELLOW WARBLER
HABITS
Along both coasts of Baja California southward from about latitude 27° N., and along the Pacific coast of Mexico from Sinaloa to Guatemala, where that curious tree, the red mangrove (Rhizophora mangle), bathes its feet in salt water along the shores of bays, estuaries, and tidal creeks, this handsome yellow warbler makes its permanent home. The red mangrove extends its growth on these muddy shores by sending its curving branches outward and downward to take root again in the mud, thus forming an almost impenetrable tangle of roots and branches in an ever-widening band extending outward from the dry land. Its dense, dark foliage forms a low, gloomy forest of branches in which this well-named warbler finds a secure retreat and to which it is almost exclusively confined. It has not always been easy to obtain in these tangles, for Brewster (1902) says that—