Page 40 - Great Blue Heron

ISSUE : Issue 17

Published by Ronald Caplan on 1977/8/1

V>ll ''Cll. ?? *" '?~' I | '| '| I o'-'iixxi'iur.jj rAui??i xi'ioxur. rnmxr uuvan -'J Stick-transfer. '. J Howling, and firmer;the accumulated filth helps to ceipent the material together." It is the male who is attached to the nest or nesting site. He spends a good deal of time there arranging the nest or posturing and displaying himself, often standing still high in the treetops or lying out across the nest as if covering eggs • trying to at? tract a female. And "once the heron claims it," write the Cottrilles, "the nest be? comes a target for a certain amount of at? tack by other herons in the vicinity. Any move toward a nest is warded off by the occupant with a startling threat display: plumes erect, neck thrust over the edge of nest, bill jabbed at intruder • emphasized by a loud clap of the mandibles and/or a vocal 'bark.' Early in the season this re? action seems to be directed toward intrud? ing birds of both sexes." This is apparent? ly common in species where both sexes look alike, and Verwey adds that the habit of solitude is still not overcome • the urge to mate is still in conflict with the urge to defend territory. Verwey reads the males actions at the nest as a ceremony of invi? tation. The Cottrilles call it "howling" and Lowe describes it this way: "Firmly grasping the nest or.branch with his claws, the bird stretches his head and neck vertically upwards to the fullest ex? tent, then lowers his neck over his back with the bill still pointed skywards, and finally, by flexion of the legs, lowers Burland Murphy with a fallen nest. his body into the nest....When he has ex? tended himself to the utmost he calls hoo and continues to gurgle -oooo as his head is brought downwards and backwards: if a female comes close he continues his pos? turing but stops calling. (A variant pat? tern, when the female is quite near:) the head is lowered in front of the bird and the mandibles snapped audibly together. Should the female stay he may snap and thrust his bill towards her, but if she flies off he begins to display again with unabated vigour." If the female returns a- gain and again, his attacks at her are less and less determined and they end up at the nest, nibbling each others' mandibles. Thus the male attracts, the female selects, the male wards her off and eventually accepts her. Cottrilles: "When a mate has been accepted by the occupant of a nest, the pair begin to perform a variety of 'courtship rituals': Erecting plumes and crest; shaking head frx3m side to side; walking around each o- ther in the nest; clapping mandible to? gether (loud hollow sound); Grasping each other's mandibles and seesawing back and forth; howling; shaking stick in nest; preening (individual and mutual); one bird stroking the other with bill on throat, nape and back." Lowe: "With the acceptance of a mate an entirely new phase begins and the ritual changes. The male becomes the stick-ga- Newly Renovated Grill at Sydney RiverI Town and Country RBSTAXJRANT Red ond White P0(??> STORES Baddeck Port Hawkesbury .A. ' Sydney River & Glace Bay Fort Havfkesbury PHARMACY operated by Mansons Prug' Ltd? OLD AS 1903: siill offering the sane old ficishion quality service tb Cape Breton* mw AS 19771 offering Drug fltns, Charge Cards?? Delivery, Mail-Order and nost Iiiti?6rt?nt