Foam Lake Birding No. 139


No. 139

            When we arrived down here one of the first things we did was go for a bird walk in the Frontera Audubon thicket to see two rare Mexican birds that were reportedly there.  One was the Crimson Collared Grosbeak; the second was the Golden Crowned Warbler.  The grosbeak had not been seen since the middle of January but the warbler was being seen daily.  After two trips into the thicket and a lot of patience we got to see this rare tropical warbler which was another “lifer’ for us.  It is a rather nondescript dark greenish bird with yellowish under parts (much like the Orange Crowned warbler) and a gold (yellow) crown patch bordered by black.  Not seeing the grosbeak was not a real disappointment as we saw it two years ago in the very same thicket but would have liked to have seen it again. 

            The Crimson Collared Grosbeak is halfway between a sparrow and robin in size.  At a glance it looks all black but upon closer examination the other colours become evident.  What I found really unusual about this bird is the difference between the female and male.  With most birds, where the sexes are different, the females are simply washed out versions of the males.    Not so with the Crimson Collared Grosbeak.  Here the sexes are just different.  The male is black with deep, dull red shoulders and breast; like the male, the female is also black but the red is replaced by a deep, dull green.  They look more like different species rather than males and females of the same species.  Like all grosbeaks they have massive seed cracking beaks with jaw muscles to match. 

            The staple food of the Crimson Collared Grosbeak is the fruit of the Potato Tree.  The Potato Tree tree is not related to the potato plant but is so named because of its resemblance to it.  This lilac bush-size evergreen has soft velvety leaves and cherry sized green berries just like a regular potato plant hence its name.  The Potato Tree is common around here and can be found in almost any mature thicket. 

            As of this writing I have not been able to get a picture of the warbler but I am still trying.  The photo of the green female grosbeak was taken two years ago when we last saw it.  Since the newspapers carry only black and white photos the colours will only be seen on my web site:  We have seen and photographed the Golden Crowned Warbler and have included the less than perfect pictures.