Merlin (Falco columbarius) Skye Christopher G. Haas Status: State Threatened
Ottawa County Park, MI June, 2009 © Carl Manning
(Click to view a comparison of Atlas I to II) A real success story, the Merlin has expanded Huron Mountain Club, both sites in Marquette County (Gysendorfer 1955, Dodge 1955). its range and numbers in Michigan since MBBA
I. A dynamic bird, this little predator combines Unfortunately it is at this time that many raptor pluck with skill, and is a master of aerial feats species, including Merlins, were experiencing a that rival even a swallow, which a Merlin is region-wide decline from reproductive failures capable of catching and consuming. A welcome caused by organochlorine contaminants. While harbinger of spring, northern atlas workers data from the early and mid-20th Century is too found Merlins to be one of the first returning sparse to assess trends from Michigan, it is birds to take up territory. Launching out of a tall likely that the species was experiencing a low pine, the male performs his flutter flight, calling point in its population in the state (Binford loudly, displaying for a nearby female. This 2006). highly entertaining show has been encountered more frequently over the past few decades as By the 1980s, populations were beginning to Merlins have steadily increased since the mid- recover and a nest in the Keweenaw Peninsula 20th century collapse of most Michigan raptor was documented (Binford 2006). The MBBA I species. gave the first complete picture of the Merlin’s
status as a breeder in Michigan; a small Distribution population largely confined to the northern Historical records suggest that breeding has long coasts, but steadily increasing by the end of the occurred in the Upper Peninsula. Adults with 1980s. Away from its stronghold on Isle Royale, flight-capable young were observed and some populations were established in Keweenaw and individuals collected in both the Porcupine Marquette Counties, and atlas workers had Mountains and on Isle Royale in July and confirmed breeding in 11 townships including August of 1904; Merlins were also found as one in Antrim County in the LP. summer residents on Neebish Island in 1910 and likely bred there (Barrows 1912). It was not Numbers continued to grow quickly in the until 1955 that the first nests were found in 1990s, with Merlins expanding or reclaiming Michigan, two in quick succession with one on territory throughout the UP and NLP. MBBA II 13 June at Middle Island Point, and a second on results show a significant increase, with birds 20 July at the mouth of the Pine River in the found in 231 blocks statewide compared to 72
© 2011 Kalamazoo Nature Center Merlin (Falco columbarius) Skye Christopher G. Haas Status: State Threatened blocks in MBBA I; a 220% increase. Range Superior sites (Chartier and Ziarno 2004, pers. expansion was highest in the UP with the obs.). A clutch of four to five eggs are laid in percentage of townships reporting Merlins early to mid-May, sometimes as late as early increasing from 9% to 26% between the two June. Incubation lasts about 30 days, and is done atlases, with a substantial movement into the primarily by the female, with the male bringing interior of the peninsula. Absent from Dickinson food to his partner and occasionally offering and Menominee Counties in MBBA I, the nest relief. The young fledge from the nest MBBA II produced six and four records about 29 days after hatching, and remain respectively for these counties dependent on adults for one to four weeks afterwards. Fledglings generally depart from the Merlins have also spread to a lesser extent in the natal area between mid-July to mid-August LP, with birds found in 30 NLP townships (Sodhi et al. 2005). compared to only five in MBBA I. Breeding was even noted along the tension zone on Lake Abundance and Population Trends Michigan with a confirmed breeding in Oceana Rich has estimated the population of Merlins in County and what appeared to be a pair of young the U.S. and Canada to be 650,000 birds (Sodhi birds possibly attended by an adult in Muskegon et al. 2005). Partners in Flight (PIF) has County, though breeding could not be estimated there to be 300 Merlins in Michigan, established by atlas criteria (J. Johnson, pers. likely an accurate number (PIF 2007). Overall, comm.). Merlins are increasing over the entire Great Lakes region. PIF has estimated 3,000 birds in Merlins prefer semi-open habitat with tall Minnesota, and 80,000 for Ontario, where the conifers for nesting, and are frequently found species has increased significantly – more than along coasts, large lakes and boglands. Nesting double between Ontario’s first and second habitat in the Keweenaw is mesic or wet mixed atlases (Gahbauer 2007). In Wisconsin, forest near large openings, usually along Great population numbers are similar to Michigan. Lakes shoreline (Binford 2006). Pine-covered New York had an impressive increase; the islands on inland lakes are preferred for nest species went unrecorded in their first atlas, yet sites in the Michigamme Highlands of Baraga was found in 131 blocks in the second and Marquette Counties. Proximity to humans (McGowan and Corwin 2008). does not seem to be a factor, and there has been a trend in both Michigan and region-wide for While Great Lakes coastlines seem to be nesting in urban locations. In the City of preferable to inland sites for nesting, there is no Marquette, multiple pairs can now be found, and attraction to water in particular. Rather, Merlins nests have been located at city parks, take advantage of the open habitats to chase and cemeteries, and on the Northern Michigan catch birds on the wing and can also be found University campus (pers. obs.). over large inland lakes, marshes, towns, and even farmland. Binford (2006) speculated that Breeding Biology the reason for concentrations of breeding In Michigan, birds seem partial to conifers for Merlins along Lake Superior may be that it nesting, usually red or white pines (Binford offers quality hunting opportunities. Birds that 2006). Merlins do not build nests, but re-use old hold such territories have an abundance of prey corvid or raptor nests with little to no items in the form of trans-lake migrants, with modification (Sodhi et al. 2005). Birds return to passerine migration beginning in August, just as breeding territories in late March and early juveniles become independent and adults are April, and as late as mid-April at some Lake relieved from parental care. It is possible that as
© 2011 Kalamazoo Nature Center Merlin (Falco columbarius) Skye Christopher G. Haas Status: State Threatened these territories are filled, more birds will push Environment Canada, Ontario Field into the less preferred, but still suitable habitat Ornithologists, Ontario Ministry of Natural in the interior of the peninsulas. Resources, and Ontario Nature. Toronto, Ontario. Conservation Needs Gysendorfer, R. 1955. Pigeon Hawk Nesting in The Merlin has adapted to the changes that have Marquette County, Michigan. Jack-Pine altered the habitat within its range, and is poised Warbler 33(4): 130-131. to continue its comeback in Michigan. Potential McGowan, K.J., and K. Corwin, editors. 2008. concerns include water quality and making sure The Second Atlas of Breeding Birds in New that contaminants are not introduced into the York State. Cornell University Press, Ithaca, ecosystem, such as that which brought about NY. their mid-20th century collapse. Another Sodhi, N.S., L.W. Oliphant, P.C. James, and potential limiting factor is prey abundance. I.G. Warkentin. 2005. Merlin (Falco Dependent upon smaller birds for food, the columbaris). In The Birds of North America, decline of many boreal species could affect nest No. 44 (A. Poole and F. Gill, eds.). The productivity. Finally, we must make sure that Birds of North America, Inc., Philadelphia, logging pressure is not too intense and that PA. mature trees in potential nesting zones are left available for this fearless and graceful raptor. Suggested Citation
Literature Cited Haas, S.C.G. 2011. Merlin (Flaco columbarius). In Chartier, A.T., J.J. Baldy, Barrows, W.B. 1912. Michigan Bird Life. and J.M. Brenneman (eds.). 2010. The Special Bulletin. Michigan Agricultural Second Michigan Breeding Bird Atlas. College. Lansing, MI. Kalamazoo Nature Center. Kalamazoo, MI. Binford, L.C. 2006. Birds of the Keweenaw Accessed online at:
© 2011 Kalamazoo Nature Center