The concluding piece in my Dalhousie diary is the story of a lovely bird called the black and yellow grosbeak (Mycerobas Icterioides) that enthralled us during our ten-day visit. The black and yellow grosbeak is a myna sized bird. The male grosbeak is a bright canary yellow with a black head while the female is entirely dull grey in colour.
There are many bird species (and other species groups too) wherein the male and female are differently coloured. This is called sexual dimorphism, wherein the male and female sexes differ. What could be the reason for this? The male bird needs to look handsome and attract the female, while the females need to hide themselves when they are nesting, and don’t want to attract any attention from predators. Hence, it is perfectly logical for the males to look good, and the females to be dull coloured.
Grosbeaks belong to the finch family of birds. They have thick, strong beaks, and are primarily seed eaters. The specialised sturdy beaks of the grosbeaks permit them to crack open seeds with thick kernels. I have watched them crack open large seeds in this manner on numerous occasions.
As is so typical in all things in nature, you come to accept a particular behaviour of a creature, then it goes and breaks the norm and decides to surprise you!
There were two pairs of grosbeaks near our home. It was obvious to us that they were nesting. We observed that the two female grosbeaks often ventured forth together to forage, while the males were normally by themselves. And while they hung around the females, they never went out to feed with the female.
Both the male and the female grosbeaks would often hop onto a wire fence, a few metres from our house, giving us an excellent view of the pretty birds from the window of our drawing room.
On many occasions, if we stepped out into the garden, the birds would give us a dirty look and fly away, as though saying “Can’t you see that we are feeding? Don’t disturb us!”
We would frequently see the grosbeaks hopping about on the ground, and I often wondered what they were eating. After they flew away, I would scan the area to check whether I could find any seeds, and to my surprise, there were none. Intrigued, I decided to watch the birds more closely.
From our home’s window, I watched a female bird hopping on the ground. She picked up something large and flew up to an oak tree near the house. Through my binoculars, I observed as the grosbeak began to feed. She had picked up a slug from the ground and was busy devouring it.
“What’s happening?” I asked myself. “This is a grosbeak, a finch; they are supposed to eat seeds and not slugs!” Over the next ten minutes, I observed and photographed the grosbeak gorge on the slug, picking the soft-bodied creature apart, and swallowing its parts. As slugs are soft bodied and slow moving, they are obviously easy to catch and eat, so the grosbeaks must have decided that this was an easy source of protein.
Over the next few days, we watched the male and female grosbeaks feed on slugs regularly; slugs had clearly become a major part of this seed-eating birds’ regular diet, at least in this season.
Clearly, the grosbeaks had not read the books that I have, which state that they like to feed only on seeds!
Feedback and queries are welcome at sanjay.sondhi1@gmail.com