Outdoor Ontario

Discussion => Behaviour => Topic started by: Bella on June 19, 2007, 04:41:24 pm

Title: Birds bumping each other
Post by: Bella on June 19, 2007, 04:41:24 pm
I'm quite a newby to birding but I thought I would have noticed this behaviour prior to now.  What is going on when birds come up under other birds and bump them while they are flying.  I saw a very small bird doing this to a rather large bird that was flying with about 4 other birds.  It flew underneath it and also right at it.
Title: Bird Behaviour
Post by: JTF on June 19, 2007, 10:17:42 pm
This is called "mobbing", even if there is only one of the smaller birds, and it's the high season for it - nesting and rearing season. Mobbing occurs in all seasons, but adult birds with young are
particularly persistent in chasing birds they consider to be a threat.  Red-winged Blackbirds are one of the most agressive and most common chasers.
Title: Mobbing
Post by: Ron Luft on June 20, 2007, 01:40:01 pm
Can be fun to watch. I've observed a pair of Red Wings at a friends farm that 'owned' half a field while a Harrier's favourite perch was in the other half. As long as the Harrier didn't cross the RW territorial property line things were quiet. The Harrier almost always flew off to the 'other' side. Red Tail Hawks can be the targets of RW and Grackles. Crows too can be harassed by them. Crows in turn are notorious for pestering Red Tails but especially the larger Owls. "Clue"...if there's a large pine with a lot of crows around making quite a ruckus...check for an owl roosting. Humans too can be targets especially of RWings. They have been known to dive at and even occasionally peck attack. One reason why smaller birds can get away with this is that in flight they are faster and more agile than bigger birds. Most of the falcons (Kestrel, Merlin, Peregrine) aren't usually harassed as they are agile and hunt birds anyway. Well observed! You'll learn a lot that way, even if it isn't scientifically accurate to 100%, it will help you be a better birder. Keep in mind that proscribed behavior isn't a 'rule'. I've seen Red Headed Woodpeckers and Scalet Tanagers on the beach at Pelee, not in trees as they 'should be'.
Title: Re mobbing
Post by: Bella on June 21, 2007, 12:43:11 pm
That is incredible!  I thought it was pretty courageous for a little bird to be taking on a bigger one but your comments on thier agility make sense of that.  It is quite a site to see.  

I remember a crow being particularly uspset with me for going too near its offspring.  It was wounded underneath some playground equipment and two boys were tormenting it so I went to its rescue.  I worked for a vet so I thought we could help it out.  Big mistake.  The mother crow was already upset that the kids were after it, but when she saw me pick it up and start taking it away she got very aggresive.  The bird did need help, it's wings were quite broken.  The mother followed me all the way home.  Her fierce squacks were punctuated by dive bombs at my head.
Post by: Kin Lau on June 21, 2007, 01:37:06 pm
For an idea of what Red-Winged Black Birds will do, I have an album in my gallery http://outdoorontario.net/Gallery/RWBB-attacks
Title: Mobbing
Post by: Bella on June 22, 2007, 01:05:59 pm
Kin Lau, those are great pics of their behaviour.  Thanks for the info.