When Push Comes to Shove
I pushed my little sister off a roof once when we were kids. It wasn’t malicious behavior. My sisters and I were filming a backyard action movie and the scene required a spectacular eight foot plunge. The youngest sister had changed her mind at the last minute and with fading light, I gently nudged her. I got the shot. Looking back it reminds me of Bald Eagle chicks and the eldest who unceremoniously shoves the youngest hatchling out of the nest. One less mouth to feed. More for me. It’s called obligate siblicide and it’s not very nice.
This behavior stands in stark contrast to the communal breeding behaviors that roughly 3% of bird species exhibit, in particular the Purple Gallinule (Porphyrio martinica). Despite being fantastically colored, the Purple Gallinule is quite shy like other members of the Rail family. I often see them in relatively high numbers at Lake Trafford in Immokalee, FL.
The marshes of Lake Trafford are dominated by the large-leafed Alligator Flag (Thalia geniculata) which creates a dense 5-12 foot herbaceous canopy for the bashful birds. Purple Gallinules can be very territorial and with good reason. Give a neighboring bird an inch and they’ll take the swamp. To combat this, Gallinule families will participate in communal breeding where a male and one or two females lay eggs early in the nesting season then lay another clutch soon after those hatch. Eventually the young from the first clutch help feed and care for the second clutch. The entire brood protects the food and shelter necessary for their survival.
Clearly their most notable feature is their plumage – an adornment of iridescent purple, green and blue that aids in courtship but screams “look at me” to predators as well. What will often go unnoticed are the long slender toes that help them walk on aquatic plants and grasp thin stalks of vegetation. Gallinules will climb several feet up to survey the area for predators, signaling the brood by flipping their white-feathered tail. In doing so they protect their family as well as themselves. Come to think of it, I’ve never seen a Purple Gallinule knock another family member of its perch.