Surprise! You may notice that the birds on the Wells Fargo osprey nest do not look like Ospreys! In fact they are Great Horned Owls. Great Horned Owls are one of the earliest nesting species in Iowa, often laying eggs in December or January, and are renowned for their ability to repurpose other birds’ nests. This year it looks like a pair of owls found the osprey platform and have hatched at least one chick who is fairly well developed at this time and will be ready for fledging soon.
Unfortunately for our osprey pair, this almost certainly means the platform will not be available for them to nest on this year. It would be dangerous for the pair to try to take over the platform from the very formidable Great Horned Owls. This is a natural situation that is just part of the life of a raptor and there is hope for next year as Great Horned Owls don’t always return to the same nest site as faithfully as Osprey tend to.
As a reminder and some history on the Ospreys that have used this site, they are the result of many years of reintroduction and recovery by Osprey in Iowa starting with the first successful nesting since European settlement at Spirit Lake and Iowa City in 2003.
In 2019, only one of the pair of birds showed back up at the nest platform after migration. No nesting occurred that year. In 2020 through 2022, it appeared that the surviving bird had found a new mate! Two birds were seen at the nest, worked hard to spruce the nest up and were even caught mating on camera at least once. However, that did not translate into successful nesting attempts. This is not unusual for a “new” pair, to not quite get their act together. Finally, in 2023 they were successfully able to hatch 3 chicks, 2 of which made it to fledging from the nest.
When young are produced, the young follow the parents to South America during migration but will then stay in the nonbreeding range for the whole year that follows. This is an evolutionary strategy that benefits the Osprey population. Most mortality occurs during migration. The young will then return to Iowa as two-year olds and will roam around Iowa until choosing a mate and nest site when they are four or five years of age.
In 2023, there were 33 Osprey nest attempts that we know about in Iowa. Sixteen of these nests were successful and produced at least 26 young. Thank you to the staff at Wells Fargo West Des Moines campus for providing the camera that allows viewers to watch this nest platform!
4/24/2024 Update
The Great Horned Owl chick fledged out of the nest last week and the osprey moved in the very next day and started laying eggs! What a transition! Things have been a little unsettled at the nest so the outcome of the nesting season is still uncertain but we've got our fingers crossed for this pair of Osprey to succeed. Stay Tuned!