Pied-billed Grebe (Podilymbus podiceps) Damon McCormick
Washington. 6/16/2008 © Jerry Jourdan
(Click to view a comparison of Atlas I to II)
To early naturalists it was the “hell-diver” or limit of the species’ range, “it nests abundantly in every suitable place in the state, from the “water-witch”, and its idiosyncrasies tended to Ohio-Indiana line to Lake Superior.” inspire hyperbole: “These peculiar little spirits Subsequent surveys in the 20th Century of the water present a very radical departure however, recorded decidedly less than abundant from what the word ‘bird’ usually brings to densities in the NLP and UP, and MBBA I mind” (Rockwell 1910). Occupying its own documented a significantly higher percentage of genus within the seven-member North breeding Pied-billed Grebes in the SLP, American Podicipedidae family, the Pied-billed particularly in southwestern counties (Storer Grebe, while by no means singularly non-avian, 1991). was not mischaracterized by its antiquated appellations. With a pattern of nocturnal Breeding Biology migration and a propensity to dive rather than Pied-billed Grebes tend to occupy fresh to fly in response to threats, the species is almost moderately brackish waterbodies greater than exclusively encountered upon the marshes and 0.2 ha, marked by dense stands of emergent ponds that constitute its summer home vegetation and ample stretches of open water (Wetmore 1924, Muller and Storer 1999). A (Muller and Storer 1999). Their cuckoo-like breeding adult, diminutive and drably adorned song – “far-carrying, vibrant, throaty barks” – in brown and gray, nonetheless demonstrates a can be vocalized by both sexes, and is strident territoriality within its wetland turf, associated with courtship and territorial responding aggressively to both intra- and inter- delineation (Deusing 1939, Muller and Storer specific interlopers (Glover 1953, McAllister 1999, Sibley 2000). Once a territory is and Storer 1963). established, a breeding pair jointly constructs a
small floating platform of aquatic vegetation, Distribution typically anchored to a stand of dense emergents The Pied-billed Grebe breeds across the such as cattails or bulrushes, and within 50 feet contiguous United States and south-central of open water (Glover 1953, Otto 1983, Canada, and is the most widely distributed Sandilands 2007). Incubation of five to seven Podicipedidae in North America (Muller and bluish- to greenish-white eggs, undertaken by Storer 1999). Barrows (1912) asserted that both adults, lasts an average of 23 days within Michigan, which approaches the northern
© 2011. Kalamazoo Nature Center Pied-billed Grebe (Podilymbus podiceps) Damon McCormick
(Deusing 1939, Glover 1953, Otto 1983, Muller Atlas efforts, and to the clandestine nature of and Storer 1999). Hatched chicks are pied-billed nest sites (in Wisconsin, 74% of semiprecocial, with showy vertical stripes along Confirmed BBA records involved observations their neck that echo the pied coloration of their of fledged young), it is probable that the parents’ bills (Muller and Storer 1999). Fed on species’ breeding activities were undercounted a varied diet of crayfish, aquatic insects, during both MBBA I and II; this likelihood, dragonfly nymphs and small fishes, young however, does not alter the significance of the spend most of their first three weeks near the substantial drop in observations between efforts nest platform; by five to six weeks they are (Brooks 2006). In response to the downtrend in typically capable of self-sufficiency and flight Michigan and across the broader Great Lakes (Wetmore 1924, Deusing 1939, Muller and region, the Pied-billed Grebe has been listed as Storer 1999). a USFWS Bird of Conservation Concern in both the U.S. portion of the Boreal Hardwood Abundance and Population Trends Transition zone, which includes the UP and As during MBBA I, the majority of MBBA II NLP, and the Prairie Hardwood Transition zone, block-level records for Pied-billed Grebes which includes the SLP (U.S. Fish & Wildlife occurred in the SLP (56% in MBBA I; 57% in Service 2008). MBBA II). Township-level breeding continuity between Atlases was low, particularly for Conservation Needs Confirmed observations: Among 29 and 22 The agricultural drainage and commercial Confirmed UP townships in MBBA I and development of state marshes, swamps and bogs MBBA II, respectively, only one location – – which eliminated an estimated 11 million within Seney National Wildlife Refuge – was wetland acres during the 19th and 20th centuries recorded during both efforts. In the SLP, gains – certainly ferried the deterioration of Pied- occurred in some southeastern counties, billed Grebe densities reported by Barrows particularly Washtenaw, while many (1912) and other early ornithologists (MI-DNR southwestern counties indicated declines, 2007). The declines experienced by the species especially within townships bordering Lake over the past 20 years have likely been Michigan. More broadly, all measures of negatively influenced by the actual statewide breeding occupancy declined management, or lack thereof, of remaining markedly between Atlases: confirmed block wetland habitat. Specifically, research evidence observations (-33%), confirmed township suggests that breeding Pied-billed Grebes observations (-32%), total block observations benefit from comparatively larger and deeper (-22%), and total township observations (-18%). marshes marked by areas of plentiful open water These findings are buttressed by a 14% annual – characteristics achieved by actively reversing decline (1983-2007) in Pied-billed Grebes excessive vegetative succession and where recorded on BBS routes throughout U.S. Fish & possible, maintaining stable water levels Wildlife Service (USFWS) Region 3 (Sauer et throughout the nesting season (Glover 1953, al. 2008), and by a 6% annual decline (1995- Osnas 2003, Harrison et al. 2008). Such 2006) documented across the Great Lakes Basin hydrologic control is, of course, not feasible on by the Marsh Monitoring Program; importantly, the Great Lakes, where a significant positive the latter project utilized broadcast tapes for correlation has been demonstrated between surveying, a method shown to improve grebe breeding Pied-billed Grebe observations at detection by 121% over passive observation survey points along Lakes Erie, Huron and (Gibbs and Melvin 1993, Harrison et al. 2008). Michigan and the water levels of those lakes, Owing to the lack of playback in Michigan which dropped considerably during the
© 2011. Kalamazoo Nature Center Pied-billed Grebe (Podilymbus podiceps) Damon McCormick monitoring period of 1997-2002; a small note of Michigan Department of Natural Resources optimism for the species’ statewide future (MI-DNR). 2007. Wetlands. involves the supposition that a rise in these
© 2011. Kalamazoo Nature Center Pied-billed Grebe (Podilymbus podiceps) Damon McCormick
Lakes Hydrology. Journal of Great Lakes Suggested Citation Research 34: 351-364. U.S. Fish and Wildlife Service. 2008. Birds of McCormick, D. 2011. Pied-billed Grebe Conservation Concern. (Podilymbus podiceps). In Chartier, A.T.,
© 2011. Kalamazoo Nature Center