DOCSLIB.ORG

BROWN-HEADED COWBIRDS: from Buffalobirds to Modern Scourge

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
BROWN-HEADED COWBIRDS: from Buffalobirds to Modern Scourge BROWN-HEADED COWBIRDS: From BuffaloBirds To Modern Scourge What is a Cowbird? nests parasitized (usually of at least several Cowbirdstend to parasitize birds smaller in size differentspecies) per female in one season. than themselves. For example, by the time they 1l1e Brown-headed Cowbird (Molothms ater) is Typically, female cowbirds find potential host are ready to leave the nest (fledge), most warbler a broodparasite that lays its eggs in the nests of nests by perchingduring early morning hoursin a or vireo nestlingsweigh lessthan half as much as other birds. These "foster parents", called hosts, locationwith high visibility such as adead tree in cowbird nestlings. In fact, a fledgling cowbird is usually raise cowbird young at the expense of a forest opening, observing behavior of host larger than the adult warblers and vireos! The theirown eggs or young. females that are building nests, and followingthe monstrous cowbird nestling not only can cause unsuspectingdirectly birds to their nests. Once host young to starve by monopolizing the food Cowbirds earned their common name from the the nest location is known, the cowbird returns supply brouglit by parent birds but also literally habit of following herds of buffalo(and cattle) in during the egg-laying period of the host female may crowd host young right out of the nest. search of the insects that were flushed up by the and depositsher own egg in the nest. large grazing mammals. Plumage of the male The combination of these parasitic habits can Brown-headed Cowbird is mostly glossy black By parasitizingduring the host egg-laying period, severely affect the host family. hnpacts of with a contrasting dark-brown head; females are the female cowbirdimproves her chancesthat the parasitismare different for differenthost species, dull grayish brown. The dull plumage of the host female will be away from the nest often but usually result in theloss of at least one, and female is thouglit to be advantageous to the (allowing the cowbird access without being often all, of the 3-5 host young. Althougli each parasite, as it potentially makes them less detected), and that the cowbird egg will be cowbird female only lays one egg in a nest, a, conspicuousto host species. acceptedby the host and receivefull incubation. high abundance of cowbirds in an area often will lead to many cowbirds parasitizing the same Althouglicowbird parasitismoccurs in almost all limited supply of host nests. The presence of habitat types, cowbirds tend to select overgrown more than one cowbird in a nest almost fields and forest edges more than other habitats inevitably leads to death of all host young. In for reproduction, and species that build open-cup addition, raising even one cowbird can nests in shmbs in these habitats are most potentially reduce the survival of host parents commonly parasitized. Because of their affinity ' becauseof the increasedphysical effortneeded to for forest edges, increases in forest edge due to care forthe ravenous intruder. forest fragmentation can increase parasitism frequencyfor many forest bird species, including Why do Hosts Tolerate the Imposters? Neotropical migrants. Some species of forest­ dwelling Neotropical migrants have been found In about60- 70% of nests parasitized,the cowbird Host species arerejecters or accepters of cowbird to sufferhigher rates of nest parasitism in small, removes one of tl1e host eggs before laying her parasitism. Rejecters recognize and remove isolated forest tracts than in large w1broken own egg. 11lis is possiblyto ensure that the host cowbird eggs from their nests immediately after forests. In addition, parasitism levels are often does not "notice" a different number of eggs in they are laid. Accepters rarely eject parasite higher in regions with highly fragmented forests the nest, or to ensure that the cowbird egg eggs, incubating cowbird eggs and feedinghuge, than in largelyforested landscapes. receives full incubation (an extra egg in the nest noisy cowbird young as if they were their own. may not allow the female to incubate all eggs Only 9 host species have beendetermined to be Portrait of a Parasite evenly). rejecters and most are birds with beaks large enougli to remove unwantedeggs easily. Cowbirds have been called songbird chickens Cowbird eggs require an incubation period of because they can lay more eggs than any other only I 1-12 days, whereas most host species wild bird. A single female is capable of laying require 12-14 days, and some asmany as17 days nearly one egg per day at the peak of the of incubation. Consequently, cowbird young breeding season, and produces a total of 30-40 hatch earlier than tl;e host young, affording the eggs over the 2-3 month breeding period (May­ parasite a distinct advantage in competing for July). Because female cowbirds usually lay only foodwith its yotmger foster siblings. one egg in a host nest, this translates into 30-40 F a c t S h e e t N o. 3 Smithsonian MigratoryBird Center Fact Sheet No. 3 Why somebirds acceptparasitism is W1clear,but and habitat use. Preferred foraging sites are FurtlierReading: it may be because they simply do not recognize livestockareas that provide bothinsect and grain parasite eggs, orattempts at removing the thick­ foods,but cowbirds alsoexploit bird feedersand shelledcowbird egg could result in breakage and refuse from campgroWlds, picnic areas, etc. lossof theirown eggs, or raising the cowbirdis a Because no parental care is given to offspring, Brittingham, M.C. and SA. Temple. 1983. better optionthan the risk of not nestingat all. cowbird foraging areas can be separate from Have cowbirds caused forest songbirds to Perhaps someaccepter species, particularly those reproductiveareas, allowing female cowbirds to decline? 33:31-35. inhabiting forests, only encoW1tered cowbird exploit a varietyof habitatsover greatdistances. parasitism in thelast 100years andso have not Cowbirds have been foW1d to commute up to 7 Friedmann,BioScienceH. 1929. evolvedto recognizeand reject the parasitism. In kmdaily between foraging and egg-laying areas. C. Thomas, essence, they are easy targets for the invading Springfield, IL. The Cowbirds:A Studyin cowbirds. the Biology of Social Parasitism. Ke11y, S.T. andM.E. Decapita. 1982. Cowbird Luckily, some accepters are able to escape How Can We Control Cowbirds and control and its effect on Kirtland's Warbler parasitism to an extent by nestingearlier or later Parasitism? reproductivesuccess. 94:363-365. than the cowbird breeding season (generally ear.lyMay to earlyJuly), or by nestingmore than Because cowbirds thrive in a human-altered WilsonBull. once during a season (at least one nest attempt landscape, there will be no easy solutions to the Mayfield, H.F. 1977. Brown-headed cowbird: probablywill not beparasitized). problem. However, some alternatives for Agent of extermination? 31:107-1 13. contro11ingcowbirds exist. Am. Birds Human-Made Problem Cowbird removal through trapping or shooting Robinson, S.K., J.A Grzybowski, S.I. Rothstein, has proven useful in the conservation of M.C. Brittingham, L.J. Petit, and F.R. Almost everything humans do in manipulatin endangered species such as the Kirtland's Thompson. 1993. Management implications of our environment is beneficial to cowbirds Warbler and Black-capped and Least BeU's cowbird parasitism on Neotropical migrant Removing or cutting into the forest for roads vireos. For these species, intensive cowbird songbirds. Pages 93-102 in D.M. Finch and settlements, or timber harvesting, for example control has drastica11y reduced the parasitism P.W. Stangel, eds.. and canimprove thehabitat for cowbirds by creatin levels that threatened to drive their populations USDA Forest grassy foraging areas, open perch sites fo to rapid extinction. However, this controversial Service, GeneralTechnical StatusReport ManagementRM-2 29. of surveyinghosts, and more access to host specie practice probably wi11 only be effective in Neotropical Migratory Birds. in edge or open forest habitats. Agricultura extreme cases such as these where host practices that leave waste grain behind durin populations are small and localized. Cowbird winter provide superior winter feeding sites fo trapping would be too costly and labor-intensive Rothstein, S.I. 1975. An experimental and cowbirds, improvingtheir annualsurvival. to be effective in the control of cowbird teleonomic investigation of avian brood parasitism on a regional basis. parasitism. 77:250-271. Historically, the range of the cowbird prior to ' ,, European settlementwas restricted to the open TI1e most effective way to control cowbird Condor short-grass prairies of the Midwest. Presumably numbers and the impact of cowbirds on as a result of large-scale deforestation, Neotropical migrants is to control the features of introduction of cattle, and other activities the environment on which they thrive. associated with European settlement, the Landscape-level measures that maintain large cowbird's range expanded rapidly eastward and forest tracts with minimal edge-to-interior ratios the species was widespread throughout the (i.e., compact versus long, linear shapes) would eastern U.S. by the late l 800's. A similar be most effective. In addition, openings in expansion occurred in the west during the forests for gas wens, picnic areas,etc., should be l 900's, resulting in their distribution being minimized and concentrated into a few areas spread throughout southern Canada and the rather than dotted throughout the forest. Such lower 48 states. Cowbird populations have
Load more

Recommended publications
  • Prairie Ridge Species Checklist 2018
    Prairie Ridge Species Checklist Genus species Common Name Snails Philomycus carolinianus Carolina Mantleslug Gastrocopta contracta Bottleneck Snaggletooth Glyphalinia wheatleyi Bright Glyph Triodopsis hopetonensis Magnolia Threetooth Triodopsis juxtidens Atlantic Threetooth Triodopsis fallax Mimic Threetooth Ventridens cerinoideus Wax Dome Ventridens gularis Throaty Dome Anguispira fergusoni Tiger Snail Zonitoides arboreus Quick Gloss Deroceras reticulatum Gray Garden Slug Mesodon thyroidus White-lip Globe Slug Stenotrema stenotrema Inland Stiltmouth Melanoides tuberculatus Red-rim Melania Spiders Argiope aurantia Garden Spider Peucetia viridans Green Lynx Spider Phidippus putnami Jumping Spider Phidippus audax Jumping Spider Phidippus otiosus Jumping Spider Centipedes Hemiscolopendra marginata Scolopocryptops sexspinosus Scutigera coleoptrata Geophilomorpha Millipedes Pseudopolydesmus serratus Narceus americanus Oxidus gracilis Greenhouse Millipede Polydesmidae Crayfishes Cambarus “acuminatus complex” (= “species C”) Cambarus (Depressicambarus) latimanus Cambarus (Puncticambarus) (="species C) Damselflies Calopteryx maculata Ebony Jewelwing Lestes australis Southern Spreadwing Lestes rectangularis Slender Spreadwing Lestes vigilax Swamp Spreadwing Lestes inaequalis Elegant Spreadwing Enallagma doubledayi Atlantic Bluet Enallagma civile Familiar Bluet Enallagma aspersum Azure Bluet Enallagma exsulans Stream Bluet Enallegma signatum Orange Bluet Ischnura verticalis Eastern Forktail Ischnura posita Fragile Forktail Ischnura hastata Citrine
    [Show full text]
  • Brown-Headed Cowbird (Molothrus Ater) Doug Powless
    Brown-headed Cowbird (Molothrus ater) Doug Powless Grandville, Kent Co., MI. 5/4/2008 © John Van Orman (Click to view a comparison of Atlas I to II) Brown-headed Cowbirds likely flourished Distribution Brown-headed Cowbirds breed in grassland, alongside the Pleistocene megafauna that once prairie, and agricultural habitats across southern roamed North America (Rothstein and Peer Canada to Florida, the Gulf of Mexico, and 2005). In modern times, flocks of cowbirds south into central Mexico (Lowther 1993). The followed the great herds of bison across the center of concentration and highest abundance grasslands of the continent, feeding on insects of the cowbird during summer occurs in the kicked up, and depositing their eggs in other Great Plains and Midwestern prairie states birds’ nests along the way. An obligate brood where herds of wild bison and other ungulates parasite, the Brown-headed Cowbird is once roamed (Lowther 1993, Chace et al. 2005). documented leaving eggs in the nests of hundreds of species (Friedmann and Kiff 1985, Wild bison occurred in southern Michigan and Lowther 1993). The evolution of this breeding across forest openings in the East until about strategy is one of the most fascinating aspects of 1800 before being hunted to near-extinction North American ornithology (Lanyon 1992, across the continent (Baker 1983, Kurta 1995). Winfree 1999, Rothstein et al. 2002), but the Flocks of cowbirds likely also inhabited the cowbird has long drawn disdain. Chapman prairies and woodland openings of southern (1927) called it “. a thoroughly contemptible Michigan prior to the 1800s (Walkinshaw creature, lacking in every moral and maternal 1991).
    [Show full text]
  • Rejection Behavior by Common Cuckoo Hosts Towards Artificial Brood Parasite Eggs
    REJECTION BEHAVIOR BY COMMON CUCKOO HOSTS TOWARDS ARTIFICIAL BROOD PARASITE EGGS ARNE MOKSNES, EIVIN ROSKAFT, AND ANDERS T. BRAA Departmentof Zoology,University of Trondheim,N-7055 Dragvoll,Norway ABSTRACT.--Westudied the rejectionbehavior shown by differentNorwegian cuckoo hosts towardsartificial CommonCuckoo (Cuculus canorus) eggs. The hostswith the largestbills were graspejectors, those with medium-sizedbills were mostlypuncture ejectors, while those with the smallestbills generally desertedtheir nestswhen parasitizedexperimentally with an artificial egg. There were a few exceptionsto this general rule. Becausethe Common Cuckooand Brown-headedCowbird (Molothrus ater) lay eggsthat aresimilar in shape,volume, and eggshellthickness, and they parasitizenests of similarly sizedhost species,we support the punctureresistance hypothesis proposed to explain the adaptivevalue (or evolution)of strengthin cowbirdeggs. The primary assumptionand predictionof this hypothesisare that somehosts have bills too small to graspparasitic eggs and thereforemust puncture-eject them,and that smallerhosts do notadopt ejection behavior because of the heavycost involved in puncture-ejectingthe thick-shelledparasitic egg. We comparedour resultswith thosefor North AmericanBrown-headed Cowbird hosts and we found a significantlyhigher propor- tion of rejectersamong CommonCuckoo hosts with graspindices (i.e. bill length x bill breadth)of <200 mm2. Cuckoo hosts ejected parasitic eggs rather than acceptthem as cowbird hostsdid. Amongthe CommonCuckoo hosts, the costof acceptinga parasiticegg probably alwaysexceeds that of rejectionbecause cuckoo nestlings typically eject all hosteggs or nestlingsshortly after they hatch.Received 25 February1990, accepted 23 October1990. THEEGGS of many brood parasiteshave thick- nestseither by grasping the eggs or by punc- er shells than the eggs of other bird speciesof turing the eggs before removal. Rohwer and similar size (Lack 1968,Spaw and Rohwer 1987).
    [Show full text]
  • Chapter 6 Appendices
    Chapter 6 Climate Change APPENDICES 2015-2025 Maryland State Wildlife Action Plan Chapter 6 Appendices 6a. Results of Maryland’s Climate Change Vulnerability Assessment for 265 Species of Greatest Conservation Need 6b. Results of Maryland’s Climate Change Vulnerability Assessment for Globally Rare Plants 6c. Climate Change Tree Atlas Adaptability Rankings for High Reliability Tree Models, Many of Which Occur in Maryland 6d. Documentation of the Climate Change Effects on Maryland Invasive Species Council List of Selected Invasive Species of Concern in Maryland 6e. Predictions of Species-Specific Habitat Shift Due to Climate Change in the Northeast 2015-2025 Maryland State Wildlife Action Plan Appendix 6a. Results of Maryland’s Climate Change Vulnerability Assessment for 265 Species of Greatest Conservation Need Climate Change Status Common Name Scientific Name Vulnerability Index Group1 (CCVI) Flatworms A planarian Paraplanaria dactyligera B Extremely Vulnerable A planarian Phagocata dissimilis sp. nov. A Moderately Vulnerable A planarian Phagocata projecta sp. nov. A Insufficient Evidence A planarian Phagocata virilis A Extremely Vulnerable A planarian Procotyla typhlops A Extremely Vulnerable A planarian Sphalloplana buchanani A Insufficient Evidence A planarian Sphalloplana cava sp. nov. A Insufficient Evidence A planarian Sphalloplana pricei A Insufficient Evidence A planarian Sphalloplana sp 1 A Extremely Vulnerable Hoffmaster's cave planarian Sphalloplana hoffmasteri A Moderately Vulnerable Freshwater Mussels Atlantic spike Elliptio
    [Show full text]
  • Nesting Aggregation As a Determinant of Brood Parasitism in Mason Bees (Osmia Spp.)
    Nesting aggregation as a determinant of brood parasitism in mason bees (Osmia spp.) Adam Groulx Master of Science in Biology Thesis submitted to the Faculty of Graduate and Postdoctoral Studies University of Ottawa A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science © Adam Groulx, Ottawa, Canada, 2016 ABSTRACT Identifying forces that affect population dynamics can allow us to better understand the distribution and abundance of animals. Both top-down and bottom-up factors can significantly influence animal populations. Mason bees (members of the genus Osmia; Hymenoptera: Megachilidae) are important pollinators for agricultural systems and are vulnerable to exploitation by brood parasites, such as kleptoparasitic wasps. High levels of nesting density have the potential to increase rates of brood parasitism by attracting larger numbers of parasites to areas with aggregations of nests. I conducted a field study in subalpine meadows at the Rocky Mountain Biological Laboratory in Colorado, USA, to assess whether mason bees suffer increased brood parasitism as the size of nesting aggregations increases. Mason bees were allowed to nest in artificial nest boxes and establish natural variations in numbers of nesting individuals within nest boxes. Nest cells constructed by bees were then checked for the presence of kleptoparasite larvae shortly after they were completed. Overall, nest cells constructed in blocks containing multiple active bees were significantly more likely to be oviposited in by brood parasites compared to cells constructed in blocks with fewer active nesting bees. This suggests that gathering in large aggregations for nesting can negatively affect populations of mason bees, given the high levels of brood parasitism observed in areas of high nesting density.
    [Show full text]
  • Polistes Wasps and Their Social Parasites: an Overview
    Ann. Zool. Fennici 43: 531–549 ISSN 0003-455X Helsinki 29 December 2006 © Finnish Zoological and Botanical Publishing Board 2006 Polistes wasps and their social parasites: an overview Rita Cervo Dipartimento di Biologia Animale e Genetica, University of Florence, via Romana 17, I-50125 Florence, Italy (e-mail: rita.cervo@unifi.it) Received 10 Dec. 2005, revised version received 29 Nov. 2006, accepted 6 May 2006 Cervo, R. 2006: Polistes wasps and their social parasites: an overview. — Ann. Zool. Fennici 43: 531–549. Severe brood care costs have favoured the evolution of cheaters that exploit the paren- tal services of conspecifics or even heterospecifics in both birds and social insects. In Polistes paper wasps, three species have lost worker castes and are dependent on hosts to produce their sexuals, while other species use hosts facultatively as an alternative to caring for their own brood. This paper offers an overview of the adaptations, strategies and tricks used by Polistes social parasites to successfully enter and exploit host social systems. Moreover, it also focuses on the analogous solutions adopted by the well-known brood parasite birds, and stresses the evolutionary convergence between these two phy- logenetically distant taxa. A comparative analysis of life-history patterns, as well as of phylogenetic relationships of living facultative and obligate parasitic species in Polistes wasps, has suggested a historical framework for the evolution of social parasitism in this group. As with avian brood parasites, the analysis of adaptation and counter adaptation dynamics should direct the future approach for the study of social parasitism in Polistes wasps.
    [Show full text]
  • Factors Influencing Shrubland Bird and Native Bee Communities in Forest Openings
    University of Massachusetts Amherst ScholarWorks@UMass Amherst Masters Theses Dissertations and Theses March 2017 Factors Influencing Shrubland Bird and Native Bee Communities in Forest Openings Henry Patrick Roberts University of Massachusetts Amherst Follow this and additional works at: https://scholarworks.umass.edu/masters_theses_2 Recommended Citation Roberts, Henry Patrick, "Factors Influencing Shrubland Bird and Native Bee Communities in Forest Openings" (2017). Masters Theses. 482. https://doi.org/10.7275/9425632 https://scholarworks.umass.edu/masters_theses_2/482 This Open Access Thesis is brought to you for free and open access by the Dissertations and Theses at ScholarWorks@UMass Amherst. It has been accepted for inclusion in Masters Theses by an authorized administrator of ScholarWorks@UMass Amherst. For more information, please contact [email protected]. FACTORS INFLUENCING SHRUBLAND BIRD AND NATIVE BEE COMMUNITIES IN FOREST OPENINGS A Thesis Presented by HENRY PATRICK ROBERTS Submitted to the Graduate School of the University of Massachusetts Amherst in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE February 2017 Environmental Conservation © Copyright by Henry Patrick Roberts 2017 All Rights Reserved FACTORS INFLUENCING SHRUBLAND BIRD AND NATIVE BEE COMMUNITIES IN FOREST OPENINGS A Thesis Presented by HENRY PATRICK ROBERTS Approved as to style and content by: ______________________________________________________________ David I. King, Chair ______________________________________________________________
    [Show full text]
  • Brown-Headed Cowbirds and Willow Flycatchers
    Brown-headed Cowbirds and Willow Flycatchers NaturalNatural HistoryHistory ofof CowbirdsCowbirds EffectsEffects onon WillowWillow FlycatcherFlycatcher ManagementManagement IssuesIssues BROWN-HEADED COWBIRD (Molothrus ater) BROWN-HEADED COWBIRD (Molothrus ater) Natural History of Cowbirds BroodBrood--parasiteparasite ExpansionExpansion ofof DistributionDistribution Cowbird colonization of the Far West, Rothstein 1994 Natural History of Cowbirds MigratoryMigratory andand ResidentResident BreedingBreeding SeasonSeason Natural History of Cowbirds Breeding Season Early AM activity Nest parasitism Prolific egg-layers Parasitize open-cup nesters Separate feeding and breeding areas Cowbird Abundance & Parasitism Rates Kern River Population 1.0 0.8 0.6 0.4 0.2 0.0 Parasitism Rate Parasitism 0 0.5 1 1.5 2 Point Ct Do cowbirds affect Southwestern Willow Flycatchers? Potential Effects of Parasitism on Willow Flycatchers NestNest abandonmentabandonment EggEgg LossLoss NestlingNestling LossLoss PopulationPopulation effects?effects? Parasitism and Desertion rates of parasitized Willow Flycatchers is highly VARIABLE in different regions. Parasitism Desertion Region rate (N) rate (N) Reference California 68% (19) 57% (14) Harris 1991 California 63% (60) 45% (38) Whitfield 1990 New 22% (129) 35% (26) Stoleson & Finch Mexico 1999 Arizona 7% (2034) 36% (14) Paradzick et al. 1999 Potential Effects of Parasitism on Willow Flycatchers NestNest abandonmentabandonment EggEgg LossLoss NestlingNestling LossLoss PopulationPopulation effects?effects? How often flycatcher young are produced in parasitized nests Arizona:Arizona: 44 outout ofof 3131 nestsnests (13%)(13%) California:California: 1818 outout ofof 133133 nestsnests (14%)(14%) Parasitism and SWFL Productivity 5.0 r KERN 4.0 PEN 3.0 2.0 y = - 0.01x + 1.73 Kern 1.0 Number Fledglings per Pai Number Fledglings 0.0 0.0 20.0 40.0 60.0 80.0 Percent of Nests Parasitized Kus et al.
    [Show full text]
  • YELLOW WARBLER (Dendroica Petechia) Sacha K
    II SPECIES ACCOUNTS Andy Birch PDF of Yellow Warbler account from: Shuford, W. D., and Gardali, T., editors. 2008. California Bird Species of Special Concern: A ranked assessment of species, subspecies, and distinct populations of birds of immediate conservation concern in California. Studies of Western Birds 1. Western Field Ornithologists, Camarillo, California, and California Department of Fish and Game, Sacramento. Studies of Western Birds No. 1 YELLOW WARBLER (Dendroica petechia) Sacha K. Heath Criteria Scores Population Trend 15 Range Trend 5 Population Size 2.5 Range Size 0 Endemism 0 Population Concentration 0 Threats 5 Current Breeding Range Historic Breeding Range County Boundaries Water Bodies Kilometers 100 50 0 100 Current and historic (ca. 1944) breeding range of the Yellow Warbler in California; occurs much more widely in migration. Breeding numbers have declined greatly, particularly in lowland areas west of the Cascade–Sierra Nevada axis, and the range has retracted broadly in the Central Valley and locally in the Owens Valley. 332 Studies of Western Birds 1:332–339, 2008 Species Accounts California Bird Species of Special Concern SPECIAL CONCERN PRIORITY Mojave River) and all of the Colorado Desert. Known elevational limits of breeding were 7000 ft Currently considered a Bird Species of Special (2134 m) on the western and 8500 ft (2591 m) on Concern (breeding), priority 2. Included on both the eastern flank of the Sierra Nevada. With few prior special concern lists (Remsen 1978, 2nd exceptions, Grinnell and Miller (1944) mapped priority; CDFG 1992). locations of individuals reported or collected dur- ing the breeding season in every county within GENERAL RANGE AND ABUNDANCE this general range.
    [Show full text]
  • Hours Spent in Preparation/Planning: 48 Hours Hours Spent at Actual Event: 18 Hours Hours Spent Recording Data After: 32 Hours Total: 98 Hours
    Busey Woods Bioblitz Report of Scientific Findings Submitted to: Kathy Barker Illinois Department of Natural Resources December 1, 2006 by Derek A. Liebert Urbana Park District Natural Areas Coordinator The results and findings of the Busey Wood Bioblitz were entered into the Illinois Natural History Survey (INHS) Mandela database under the oversight of database creator Gail Kampmeier. After UPD staff and volunteers spent much time verifying the authenticity of identifications and working with Kampmeier to make updates to the taxonomy of the new species identified and added to Mandela database, the final species count for the Bioblitz totaled 1327 species. The attached Mandela generated report shows the breakdown and distribution of species according to Kingdom and Major Groups. Among these, scientists discovered 738 invertebrates (611 insects), 378 higher plants, 62 fungi, 54 birds, 30 fish, 13 mammals, and 4 amphibians. It is notable that invertebrates accounted for over ½ of all species identified with higher plants adding considerably to that total. Such results are in keeping with the pyramidal trophic distribution of species fundamental to the ecological sciences. Kampmeier’s attached report draws some additionally interesting comparisons between the findings of the Busey Woods blitz of 2005 and that of the Allerton Bioblitz of 2001, in which although just a fraction of Allerton in size, Busey Woods provided similar results across many of the major groups. Beyond Kampmeier’s comparisons, the results from such a study offer many opportunities for the UPD’s environmental education staff to communicate and generate enthusiasm among its residents for the diversity of organisms that are present in a relatively small woodland—right in their own backyards.
    [Show full text]
  • Grackles and Cowbirds
    Grackles and Cowbirds Grackles The Grackle is about 12 inches in length. The Grackle appears all black at a distance, but is actually highly iridescent, with colors varying from blue to purple to green to bronze, depending on the light. Grackles have bright yellow eyes. Female grackles are duller and somewhat smaller than male grackles. Grackles are protected by the Migratory Bird Treaty Act, a federal mandate. Grackles can cause a variety of bird control problems. When Grackles are in their flocking phase, thousands of these birds can literally overwhelm trees or buildings in an area. Grackles have become one of those readily adaptable species to urbanized areas. They are intelligent birds that consistently outwit the tools utilized to scare them away. The City of San Antonio first attempted displacing roosting grackles ten years ago, by dropping firecrackers into galvanized metal trash cans placed under the trees. The birds just moved to the next tree. Next the city began using noise-making "cracker shells" fired from shotguns, with shotgun-wielding crews deployed to different parts of the city to chase grackles from tree to tree. The grackles simply moved to another location. City of Frisco Animal Services Division Cowbirds The brown-headed cowbird is a member of the blackbird family. The adult male is easily identified by his brown head and metallic green-black body. Female cowbirds are a pale brown with a gray-brown head. Both males and females have a length of about 7½ inches. Cowbirds are called brood parasites because they lay their eggs in the nests of other birds and do not care for their own young.
    [Show full text]
  • P0802-P0805.Pdf
    802 SHORT COMMUNICATIONS The Condor962702-805 0 The CooperOrnithological Society 1994 ACTIVITY, SURVIVAL, INDEPENDENCE AND MIGRATION OF FLEDGLING GREAT SPOTTED CUCKOOS ’ MANUEL SOLER, Jo& JAVIER PALOMINO AND JUAN GABRIEL MARTINEZ Departamento de Biologia Animal y Ecologia, Facultad de Ciencias, Universidadde Granada, E-18071 Granada, Spain JUANJosh SOLER Department of Zoology, Uppsala University, Villaviigen9, S-772 36 Uppsala, Sweden Key words: Broodparasitism;Clamator glandarius; description of the study site is given in Soler (1990) Great SpottedCuckoo; magpie; parental care:Pica pica; and Soler et al. (in press). post-fledgingdependence. In all nests found, chicks were banded with num- bered aluminium rings (Spanish Institute for Nature Parental care of fledglingstends to last at least as long Conservation-ICONA). In 1991, a total of 19 Great as that of nestlings, and in some casestwice as long Spotted Cuckoo chicksreared in 13 parasitizedmagpie (Skutch 1976). The post-fledging dependence period nests were fitted with radiotransmitters. In 1992, 21 (hereafter called fledalina DeiiOd)is critical for iuvenile cuckoochicks and four magpiechicks were radio-tagged. survival (Royama 1$66rSullivan 1989) and the prob- In 1992, only one cuckoo chick in each nest was pro- ability of survival to independence appears to be an vided with a radiotransmitter and all were weighed adequate estimate of relative probabilities of survival with a 300 g Pesola spring balance one or two days to breeding in many bird species(Magrath 1991). before they left the nest. Other cuckoo chicks in these For avian brood parasites,very little is known about nestswere given a unique combination of color bands the behavior of foster parents in relation to their fledg- to enable individual recognition.
    [Show full text]