From Twitter
Radisson - for anyone still wondering about the two unhatched eggs .... this is not unusual for Ella, and interestingly not for her mother Hurricane either. Ella's 1st year, 1 out of 4 eggs hatched, next year 3 of 4, last year, 2 of 4 and this year, 2 of 4 again.
Hurricane and her mates had 30 chicks fledge over the 12 years she nested here at the McKenzie building and she certainly contributed to the peregrine population. 
In 2009 the first year she nested here they had four chicks who all fledged. Also, Ella had three siblings and they all fledged. I think she did very well here! 
Ah, now this is where the question of what metric should be used to gauge "success". First is to define "success". From a species population perspective, a bird is successful if its offspring have offspring that fledge. Makes sense, that's the passing along of genetics to another generation but it doesn't consider the challenges individual birds/pairs face each year. On the other hand, looking on an annual basis, a bird that comes back, finds a mate, defends a nestsite and raises any number of chicks and migrates out is a success - but it is a more personal success for the bird.
I like both because they look at different things. The Project works to support the annual success in the hope that it translates into success at the species population level.
As RCF says, Hurricane was the resident female in Brandon for 12 years, had four mates and fledge out 30 young, an impressive personal accomplishment for any bird.
Here's how the McKenzie Seeds females stack up against each other - and I'm adding Ella in for comparison. These numbers are averaged over the number of years the individual females nested.
Note: for comparison, the average number of young (fledges) per successful pair in the US Midwest is 2.9.
| bird | eggs
per year | hatches
per year | fledges
per year | survivors
per year | returned
to nest |
|
| Bee | 3.0 | 1.0 | 1.0 | 0.0 | 0 |
| Phoebe | 3.4 | 3.3 | 3.3 | 2.9 | 8 |
| Ita | 4.0 | 0.0 | 0.0 | 0.0 | 0 |
| Holly | 3.2 | 2.8 | 2.8 | 2.8 | 5 |
| Hurricane | 3.7 | 2.8 | 2.5 | 1.9 | 4* |
| Ella | 4.0 | 2.0 | 1.5 | 1.5 | 0** |
* we stopped banding at McKenzie Seeds in 2017 so we can't be positive of the number of birds that survived to migrate, but we didn't have any unbanded birds reported injured/dead in western Manitoba that might be one of the McKenzie Seeds chicks.
** it is early days for any of Ella's kids to return to nest somewhere, so this number will hopefully change as time goes along
Sorry - missed explaining that a "survivor" is a chick that fledges and that doesn't die before December the year it hatches. In this case I am assuming that a chick is alive unless we know it has died. "Returned to nest" is only the birds we know about, could be higher - this is the passing down of genetics part.
