Des Moines and Cedar Rapids can lay claim to nesting sites for Iowa’s big three raptors–peregrine falcons, bald eagles, and recently, ospreys. The re-appearance of the fish-eating osprey has continued to slowly expand its presence in Iowa from the initial release of a five 42-day-old chicks at Lake Macbride in 1997 by the Macbride Raptor Project and the Iowa Department of Natural Resources (DNR).
“It takes a long time to grow osprey numbers,” said Pat Schlarbaum, wildlife diversity technician with the Iowa DNR. “We strive for having a minimum of three nest pairs to sustain a population; five pairs to make it secure. We have six pairs in the Des Moines metro area so things are looking up.”
Young ospreys were brought to Iowa from nests in Minnesota and Wisconsin. At 42 days old, osprey could not yet fly but they could tear fish apart on their own. After 10-14 days, they would fledge and it is at that time when they imprint on the area that they will consider as their home.
“This really is a remarkable story,” he said. “They migrate 4,000 miles roundtrip from Iowa to Central and South America, and then after more than a year away, find their way back to Iowa to nest.”
There were two successful nestings in 2003 - at Spirit Lake and Lake Macbride - which were the first documented osprey nests since before European settlement. Since then, the number of nests has continued on a trend of slow growth to now possibly more than 25 nesting pairs statewide. Schlarbaum said Iowa may be home to four new nesting pairs this year, and possibly more.
One second year nest on the Wells Fargo campus in West Des Moines has captured the interest of many as the osprey’s exploits can be seen around the world at https://www.iowadnr.gov/ospreycam. The high profile pair has produced three eggs, which should begin hatching during the first part of June.
“This is reality TV in the flesh,” he said.
Their nest building exploits has caused viewers to send Schlarbaum emails asking him to get certain items out of the nest, for fear that the birds or chicks could get hurt or entangle themselves in the materials.
“The nest exhibits all the character of the bird. They use a bunch of different stuff, like metal bands used to bind lumber, corncobs or roots, arrows, string and rope, plastic mesh and even indoor/outdoor carpeting,” he said. “It’s interesting to see what materials they use for their nests, but we keep our distance and have not intervened at this time.”
Continued slow growth has crossed an important biological threshold in Des Moines and, with four nesting pairs, in Iowa City. Cedar Rapids has added a nesting pair near downtown not far from the eagle nest and their peregrine falcon site.
“This project would not have been successful without local county conservation partners, avid birders, local businesses and anglers who donate fish for these birds,” he said. “Our role was to steward the birds to the local partners and they took it over from there. All credit goes to osprey stewards that promote clean water.”