Kin selection and reciprocity in flight formation?
|
|
- Mervin Moris Grant
- 6 years ago
- Views:
Transcription
1 Kin selection and reciprocity in flight formation? Behavioral Ecology Vol. 15 No. 1: DOI: /bheco/arg109 Malte Andersson and Johan Wallander Department of Zoology, Göteborg University, Box 463, SE Gothenburg, Sweden The reasons for conspicuous V and other flight formations in birds are debated. Theory and recent empirical advances show that energy saving is one important function of flight formations, but some aspects remain poorly understood. Combining theories of animal flight and sociality, we suggest that some of the variation in flight formations has its base in kin selection and reciprocation. The bird leading an acute V formation saves less energy than does the trailing participants. The disadvantage of leading is reduced in more obtuse formations, and when the longitudinal distance between neighbors is small, the leading bird can save about as much energy as others. Therefore, acute V formations are predicted to occur mainly in circumstances conducive to kin selection or reciprocity. These mechanisms seem possible, for example, in small flocks of adults with offspring, such as in swans, geese, and cranes. Inclusive fitness advantages may then favor an energetically expensive leader role for adults. In small groups, reciprocity is also possible among unrelated adults that recognize each other and take turns leading the V formation. In contrast, obtuse formations are expected in large flocks of unrelated individuals, such as spring flocks of waders migrating long distances. Possibilities for testing these ideas are discussed. Key words: aerial parental care, bird migration, energy saving, kin selection, prediction, reciprocity, shape variation, testing, theory, V formation. [Behav Ecol 15: (2004)] AV formation of migrating swans, geese, cranes, cormorants, pelicans, flamingos, or other large birds is a spectacular sight that gives rise to interesting questions. Why such regular formations? Most smaller birds that migrate in flocks do so in less ordered groups (Alerstam, 1990). What is the advantage of V formation (Figure 1), and why do mainly large birds use them? At least two hypotheses may explain such formations: energy saving and communication (for review, see Alerstam, 1990; Speakman and Banks, 1998). Energy saving is well supported both theoretically (see Badgerow and Hainsworth, 1981; Hummel, 1995; Lissaman and Shollenberger, 1970) and empirically (see Badgerow, 1988; Cutts and Speakman, 1994; Hainsworth, 1987, 1988; Hummel, 1995; Speakman and Banks, 1998). Weimerskirch et al. (2001) showed that great white pelicans (Pelecanus onocrotalus) have lower heart and wing beat rate, glide more often, and save as much as 11 14% energy when flying in the vortex wake from another bird (Figure 2). Flight formation may also enhance communication and orientation of the flock (see Cutts and Speakman, 1994; Gould and Heppner, 1974; Hainsworth, 1988; Hummel, 1995; Speakman and Banks, 1998). The evidence for this function is weaker than for energy saving, but both mechanisms might work together. Still, several interesting aspects of flight formations remain poorly understood, such as their variation in occurrence, size, and form. Theory suggests that large birds make greater energy savings than do small birds by formation flight (see Alerstam, 1990). Yet, not all large long-distance migrants use formation flight. Groups of raptors often soar high together with cranes or pelicans in thermal uplifts during migration, but raptors rarely use formation flight. Other species often leave the uplift in conspicuous formation (Alerstam, 1990). Why don t raptors use flight formations? Other questions concern formation shape. Swans, cranes, large geese, and other large birds often use acute V formation Address correspondence to M. Andersson. malte.andersson@ zool.gu.se. Received 22 November 2002; revised 22 February 2003; accepted 12 March (Figure 1) (see Badgerow, 1988; Speakman and Banks, 1998). The trailing birds, in contrast with the leader, can make substantial energy savings (Hummel, 1995; Weimerskirch et al., 2001). Other species use more obtuse or bow formations (Hummel, 1995), in which the leading bird is only a little ahead of its nearest neighbors, the longitudinal distance between neighbors increasing along the arms of the formation (Figure 3). In such formations, energy savings are probably more equable (Hummel, 1995). Why is there such variation in formation shape? We suggest that the variation is related to flock kinship structure and to reciprocity that depends on group size. Acute V formations may often include relatives, in particular parents and offspring and siblings. Gains in inclusive fitness might make parents willing to accept a less favorable lead position, if their relatives will benefit. Reciprocity, with individuals taking turns at the lead position, may also be involved. Energetics of flight formation In the wake of an aircraft, two counter-rotating trailing vortices create air downflow behind the wingtips, and uplift outside the wake (see Hummel, 1995; Lissaman and Shollenberger 1970) (Figure 2). The vortices are a grim reality; they can approach tangential velocities of 100 m/s and extend many kilometers behind a heavy aircraft, horizontal tornadoes with sometimes disastrous consequences for other planes that happen to fly into them. Under controlled conditions, however, a trailing plane can save much energy by suitable lateral positioning in the upwash behind the leading plane (Chichka et al., 1999; Hummel, 1973, 1995). Photographs of the wake of birds flying in clouds of helium bubbles also show that birds leave two trailing vortices (see Pennycuick, 1989; Spedding, 1987). The birds in a flock can therefore fly more cheaply in V formation, saving energy in the uplift from the frontal neighbor (see Hummel, 1995; Lissaman and Shollenberger, 1970; for review, see Alerstam, 1990; Norberg, 1990; Speakman and Banks, 1998). Lateral distance strongly influences energy savings (Chichka et al., 1999; Hummel, 1995; Lissaman and Shollenberger, 1970). Behavioral Ecology vol. 15 no. 1 Ó International Society for Behavioral Ecology 2004; all rights reserved.
2 Andersson and Wallander Kin selection and reciprocity in flight formation? 159 Figure 2 A vortex is formed in the wake of each wingtip, creating downflow behind the wing and uplift outside the wake, as indicated at the tip of the right wing of the right-hand bird. A trailing bird can take energetic advantage of this uplift by flying at a suitably lateral position relative to the bird ahead. Theory suggests that the optimal wingtip overlap for the trailing bird is about one tenth of the wingspan b. A distance of about 0.78b separates the centres of the two trailing vortices from a bird or aircraft. Figure 1 V formation flights, the upper one with an obtuse formation angle, a.90. In the lower figure, the greater spacing between birds in the longitudinal (flight) direction leads to an acute formation angle, a,90. Theory suggests that the lateral distance, d, between the centres of the two trailing vortices is less than the wingspan, b (Figure 2), the approximate relation being d ¼ bp/4 ¼ 0.78b (Badgerow and Hainsworth, 1981). In theory, a bird gains the greatest benefits if its wingtip overlaps laterally with that of the bird in front (Figure 2), as described by the optimal wingtip spacing (negative, as the wings overlap): S opt ¼ (0.78b b)/ 2 ¼ 0.11b (Badgerow and Hainsworth, 1981). Energy saving decreases rapidly with increasing lateral distance (Badgerow and Hainsworth, 1981; Hummel, 1973, 1995). The longitudinal distance between individuals that minimizes the total energy expended by the flock is debated (see Hainsworth, 1987; Higdon and Corrsin, 1978; Speakman and Banks, 1998), but it is probably less critical than lateral distance (Chichka et al., 1999; Hummel, 1995; Speakman and Banks, 1998). For individual birds, however, energy saving can vary strongly depending on longitudinal distances (Figure 3). In an acute V with long distances, the leading bird makes little or no energy saving (Hummel, 1973, 1995; Weimerskirch et al., 2001). A mathematical model of energy savings in relation to lateral and longitudinal position (Hummel, 1973) shows that energy savings are more equable in bow formation, in which trailing neighbors are closer to the leader (Figure 3). As there is a slight upwash preceding each bird, with short longitudinal distances the leader can benefit from lift generated by the trailing neighbors. Owing to longitudinal variation in the concertina-wake from wing strokes (see Pennycuick, 1989; Spedding, 1987), and to potential effects of phase relationships between neighbors, it seems likely that longitudinal position is more critical in birds than in fixed-wing aircraft (see Hainsworth, 1987). This may be why there are often longitudinal distances of several bird lengths between neighbors in an acute V formation, although such long distances are probably unfavorable for the leader. A follower may fly most cheaply at some optimal point up to several bird lengths behind the neighbor ahead, at least in large species with high flight speed, slow wing beats, and long distance between successive equal-phase wake points. This aspect may be testable in wind tunnels (see Pennycuick et al. 1997) in species such as red knot (Calidris canutus) (Kvist et al., 2001; Piersma et al., 1990). Theory suggests that if formation members differ in size, energy savings will be particularly high for small light individuals, for example, juveniles, or females in species with sexual size dimorphism (Hummel, 1995). Not all flock migrants use regular V formations or echelons (see Alerstam, 1990; Heppner, 1974). In passerines and other birds with short relative wing length, their rapid, largeamplitude wing strokes create complex wake patterns that may prevent energy saving by formation flight (Hummel, 1995). Kin selection and reciprocity We suggest that kin selection (Hamilton, 1964) plays a role in flight formations of related birds. Although the leading position in acute V formation is energetically more expensive than are other positions, the leader may gain inclusive fitness if the followers are close relatives such as offspring or siblings. Likely candidates are small flocks of geese, swans, cranes, or other large birds that migrate in family groups of parents and young (see Alonso and Alonso, 1993; Ely, 1993; Prevett and MacInness, 1980; Scott, 1980). The behavior of the leading bird may then be a form of aerial parental care. The advantage for young can be large if they are smaller and lighter than are adults (see above), as is usually the case (see Cramp and Simmons, 1977). Kin selection may also occur in flocks of several families migrating together. In waterfowl with female-biased philopatry (Anderson et al., 1992), related females often breed near each other, and there is evidence that mothers, daughters, and sisters can recognize each other as adults (see Andersson and Åhlund, 2000; van der Jeugd et al., 2002). In some arctic geese, wintering adults and offspring in extended family groups may contain members from more than two generations (Ely, 1993). Migrating flocks of swans or geese may consist of several related females and their mates, plus offspring from several years (Warren et al., 1993). Reciprocation (Trivers, 1971) can occur in flight formations if individuals take turns as leader, sharing the energetic disadvantage of the front position. Reciprocity can most easily evolve in small groups in which individuals interact repeatedly over long time (Axelrod and Hamilton, 1981; Boyd and Richerson, 1988; Trivers, 1971; for review, see Dugatkin, 1997). Large group size tends to favor defecting individuals that avoid costly behavior (Boyd and Richerson, 1988). Acute formations and reciprocity are therefore expected mainly in small stable groups with individual recognition. Recognition facilitates punishment of a free-loader that avoids taking the
3 160 Behavioral Ecology Vol. 15 No. 1 expensive lead position, for example, by mobbing it in the air or, perhaps more likely, at stopover sites. Reciprocity and kin selection can have strong synergistic effects in small groups (Axelrod and Hamilton, 1981; Boyd and Richerson, 1988) and may be particularly likely in migrating flocks of extended families. Such flocks may be teams in the sense of Anderson and Franks (2001). In large flocks of unrelated individuals, acute formation shape that saves little energy for the leader may not be stable. If the nearest neighbors lag behind at positions that benefit them but not the leader, it may easily reduce flight speed so far below the optimum that the trailing neighbors will catch up. The leader therefore has an easy means of achieving a more egalitarian obtuse formation. This applies also for other birds in the formation relative to their nearest followers. Such adjustments of longitudinal distances may contribute to the dynamic nature of large formations of migrating eiders (Somateria mollissima) and Branta geese, which may have several local and varying leading points. Such points may perhaps also contain related or familiar birds among which kin selection or reciprocity can operate locally within the larger flock. The scope for leader adjustment of the distance to followers may be a major reason why obtuse V, echelon, or bow formations occur in many birds flying in large flocks, for instance, arctic geese (Branta and Chen), sea ducks such as eiders (Alerstam, 1990), and also many waders (Piersma et al., 1990). During the many 1000 km nonstop migrations over open ocean by some waders (Piersma and Gill, 1998), energy saving is probably crucial for each individual. Large flocks of such long-distance migrants are therefore expected to fly in energetically equable, obtuse formations (Figure 1) or bows in which all individuals make similar energy savings (Figure 3). No raptors use V formation, perhaps because selection for hunting efficiency prevents dense flocking and therefore also formation flight. But raptors do not migrate in formations, not even when leaving thermal uplifts at great height on migration, when hunting is probably no option. Lack of flight formation in raptors may in part depend on their lack of kinrelated social structure after the breeding season, when they lead solitary lives. Alternative explanations The angle of a V formation may be related to relative neck length for reasons of optical contact, long-necked birds such as cranes and geese using acute formations, and short-necked species using more obtuse formations (Hummel, 1995). Neck length and communication, however, do not seem to explain the longitudinal distances between neighbors in, for example, geese, which are often much longer than a bird length (see Speakman and Banks, 1998). Small birds will probably save relatively less energy by V formation than do large birds, in which flight formations are more common (see Alerstam, 1990). But there is no obvious reason why small birds might not benefit as much from coordination and orientation by formation flight as do larger birds. The lack of V formations in small flock-migrating passerines therefore suggests that communication is not the major function of formation flight. Formation shape may depend on body size if the slower wing strokes of large birds permit closer approach to optimal positions in a formation (see Hummel, 1995), perhaps explaining why acute V formation may be more common in, for example, large geese than in small geese (Badgerow and Hainsworth, 1981; Speakman and Banks, 1998). Another possible reason is that smaller species tend to occur in larger flocks, in which kin selection or reciprocity seem less likely to favor individuals that accept an expensive leader role. Figure 3 Energy savings are unequally distributed among individuals in an acute V formation (top), the leading bird expending more energy than the others. A bow-shaped formation (bottom) is more egalitarian, and the frontal birds owing to uplift from their neighbors can make similar energy savings as the birds farther back in the formation. The average energy gain is similar for both formations, as the number of birds and the distance between wingtips are similar (modified from Hummel, 1995). Predictions and possibilities for tests The previous ideas predict that small flocks containing relatives will often use acute formations in which the leader saves little or no energy. Energetically more equable obtuse or bow-shaped formations are predicted when there is little possibility for kin selection or reciprocity among individuals that recognize each other. These ideas are testable by analysis of the occurrence and shape of flight formations in relation to flock size and kinship structure. Formation shape is expected to differ between flocks of small to moderate size, especially those containing related individuals (e.g., geese and cranes) (Alonso and Alonso, 1993; Prevett and MacInnes, 1980), and larger flocks of mostly unrelated individuals, such as spring-migrating waders and arctic geese (see Alerstam, 1990; Piersma et al., 1990). To critically test these ideas, quantitative observations of formation shape are needed, which may be possible to obtain at suitable migration stations or in overwintering areas (see Speakman and Banks, 1998). Age and sex distribution are expected to influence formation shape. Homogeneity in age, sex, and body size is expected to favor more egalitarian formations than do mixed flocks of, for example, adults and young. Offspring of the year are often smaller than parents and may be less able to
4 Andersson and Wallander Kin selection and reciprocity in flight formation? 161 maintain as high speed in lead position as larger adults can. Being smaller, juveniles can also make greater energy savings by following larger adults than vice versa (see above). Juveniles are therefore expected not to lead acute V formations. In contrast, a larger parent might help its offspring (see above) and increase flock speed by taking the lead position in an acute V. If, however, the birds are unrelated and adults have markedly higher optimal flight speed (Hedenström and Alerstam, 1995) than juveniles, adults may obtain higher fitness by forming their own flocks. Some of these predictions can be tested in species in which juveniles differ markedly in coloration from adults, for instance, swans and pelicans. Flight formation structure can be measured in photographs taken by a vertically directed camera (Speakman and Banks, 1998). Kin structuring may be detectable by analysis of the positions of adults and juveniles in formations, to see if there are suggestive nonrandom patterns, for example, with adults helping offspring to energysaving positions. Family structuring seems likely if the formation is led by one or two adults followed by a number of juveniles, then one or two adults again followed by juveniles, etc. General differences in flock kinship structure between species, and between parts of the year within species, may also be revealing. Field studies have greatly clarified formation structure and function, corroborating the hypothesis of energy savings (see Badgerow, 1988; Cutts and Speakman, 1994; Hainsworth, 1987, 1988; Speakman and Banks, 1998; Weimerskirch et al., 2001). There are observations of changes in position near the formation front (see Hummel, 1995), but quantitative data on shifts in leader position and on distances between individuals are needed. Observations on roles in flight formation in relation to age, sex, season, and other aspects are also desirable. A possible test of the relative roles of kin selection and reciprocity is to see if parents always take the expensive lead position in single-family flocks, or if there are shifts between parents and offspring or siblings. In the latter cases, there is reciprocation, although kin selection is probably also involved. Such tests might be possible with flocks of birds trained to follow a car, boat, or light aircraft (see Weimerskirch et al., 2001). Whether reciprocation alone, without kin selection, suffices for development of acute leader-expensive formations may be tested during spring migration in some species. For example, spring flocks of waders (Piersma et al., 1990) seem less likely to contain a high proportion of close relatives than, for example, autumn-migrating small groups of geese, swans, and cranes. Kin selection may therefore be negligible in wader flocks in spring (but this needs to be tested). Reciprocation probably requires small groups in which individuals recognize each other (see above). If, therefore, large flocks of adult waders use equable flight formations but small flocks use leader-expensive acute formations, this suggests that reciprocation may suffice for development of acute flight formations. We thank Donald Blomqvist, Frank Götmark, Henk van der Jeugd, and two referees for helpful suggestions on the manuscript, and the Swedish Research Council for funding (M.A.). REFERENCES Alerstam T, Bird migration. Cambridge: Cambridge University Press. Alonso JA, Alonso JC, Age-related differences in time budgets and parental care in wintering common cranes. Auk 110: Anderson C, Franks NR, Teams in animal societies. Behav Ecol 12: Anderson MG, Rhymer JM, Rohwer FC, Philopatry, dispersal, and the genetic structure of waterfowl populations. In: Ecology and management of breeding waterfowl (Batt BDJ, Afton AD, Anderson MG, Ankney CD, Johnson DH, Kadlec JA, Krapu GL, eds). Minneapolis: University of Minnesota Press; Andersson M, Åhlund M, Host-parasite relatedness shown by protein fingerprinting in a brood parasitic bird. Proc Nat Acad Sci USA 97: Axelrod R, Hamilton WD, The evolution of cooperation. Science 211: Badgerow JP, An analysis of function in the formation flight of Canada geese. Auk 105: Badgerow JP, Hainsworth FR, Energy savings through formation flight? A re-examination of the vee formation. J Theor Biol 93: Boyd R, Richerson PJ, The evolution of reciprocity in sizable groups. J Theor Biol 132: Chichka DF, Speyer JL, Park CG, Peak-seeking control with application to formation flight. In: Proceedings of the 38th Conference on Decision and Control, Phoenix, Arizona; Cramp S, Simmons KEL (eds), The birds of the Western Palearctic, vol 1. Oxford: Oxford University Press. Cutts CJ, Speakman JR, Energy savings in formation flight of pink-footed geese. J Exp Biol 189: Dugatkin LA, Cooperation among animals: an evolutionary perspective. New York: Oxford University Press. Ely CR, Family stability in greater white-fronted geese. Auk 110: Gould LL, Heppner F, The vee formation of Canada geese. Auk 91: Hainsworth FR, Precision and dynamics of positioning by Canada geese flying in formation. J Exp Biol 128: Hainsworth FR, Induced drag savings from ground effect and formation flight in brown pelicans. J Exp Biol 135: Hamilton WD, The genetical evolution of social behaviour I, II. J Theo Biol 7:1 52. Hedenström A, Alerstam T, Optimal flight speed of birds. Phil Trans R Soc Lond B 348: Heppner FH, Avian flight formations. Bird-Banding 45: Higdon JJL, Corrsin S, Induced drag of a bird flock. Am Nat 112: Hummel D, Die Leistungsersparnis beim Verbandsflug. J Orn 114: Hummel D, Formation flight as an energy-saving mechanism. Israel J Zool 41: Kvist A, Lindström Å, Green M, Piersma T, Visser GH, Carrying large fuel loads during sustained bird flight is cheaper than expected. Nature 413: Lissaman PBS, Shollenberger CA, Formation flight of birds. Science 168: Norberg UM, Vertebrate flight. Berlin: Springer. Pennycuick CJ, Bird flight performance. Oxford: Oxford University Press. Pennycuick CJ, Alerstam T, Hedenström A, A new lowturbulence wind tunnel for bird flight experiments at Lund University, Sweden, J Exp Biol 10: Piersma T, Gill RE, Guts don t fly: small digestive organs in obese bar-tailed godwits. Auk 115: Piersma T, Zwarts L, Bruggemann JH, Behavioural aspects of the departure of waders before long-distance flights: flocking, vocalizations, flight paths and diurnal timing. Ardea 78: Prevett JP, MacInness CD, Family and other social groups in Snow geese. Wildl Monogr 71:1 46. Scott DJ, Functional aspects of prolonged parental care in Bewick s swan. Anim Behav 28: Speakman JR, Banks D, The function of flight formation in Greylag geese Anser anser: energy saving or orientation? Ibis 140: Spedding GR, The wake of a kestrel in flapping flight. J Exp Biol 127:59 78.
5 162 Behavioral Ecology Vol. 15 No. 1 Trivers RL, The evolution of reciprocal altruism. Q Rev Biol 46: van der Jeugd HP, van der Veen IT, Larsson K, Kin clustering in barnacle geese: familiarity or phenotype matching? Behav Ecol 13: Warren SM, Fox AD, O Sullivan P, Extended parent-offspring relationships in Greenland white-fronted geese (Anser albifrons flavirostris). Auk 110: Weimerskirch H, Martin J, Clerquin Y, Alexandre P, Jiraskova S, Energy saving in flight formation. Nature 413:
S36-1 The flight energetics of barnacle geese (Branta leucopsis) under wild and captive conditions
52(Supplement): 627 632, 2006 S36-1 The flight energetics of barnacle geese (Branta leucopsis) under wild and captive conditions C M BISHOP 1,a, S WARD 2,b, A J WOAKES 2, P J BUTLER 2 1 School of Biological
More informationMate protection in pre-nesting Canada Geese Branta canadensis
Mate protection in pre-nesting Canada Geese Branta canadensis I. P. JOHNSON and R. M. SIBLY Fourteen individually marked pairs o f Canada Geese were observedfrom January to April on their feeding grounds
More informationIMMIGRATION IN A SMALL POPULATION OF SNOW GEESE STEPHEN R. JOHNSON. LGL Limited, nd Street, Sidney, British Columbia V8L 3Y8, Canada
The Auk 112(3):731-736, 1995 IMMIGRATION IN A SMALL POPULATION OF SNOW GEESE STEPHEN R. JOHNSON LGL Limited, 9768 2nd Street, Sidney, British Columbia V8L 3Y8, Canada A STRACT.--The Lesser Snow Goose (Chen
More informationThe wing of Archaeopteryx as a primary thrust generator
Page 1 of 5 The wing of Archaeopteryx as a primary thrust generator Nature 399, pp. 60-62 (1999) Macmillan Publishers Ltd. PHILLIP BURGERS* AND LUIS M. CHIAPPE * San Diego Natural History Museum, PO Box
More informationAccepted Manuscript. News & Views. Primary feather vane asymmetry should not be used to predict the flight capabilities of feathered fossils
Accepted Manuscript News & Views Primary feather vane asymmetry should not be used to predict the flight capabilities of feathered fossils Xia Wang, Robert L. Nudds, Colin Palmer, Gareth J. Dyke PII: S2095-9273(17)30453-X
More informationINHERITANCE OF BODY WEIGHT IN DOMESTIC FOWL. Single Comb White Leghorn breeds of fowl and in their hybrids.
440 GENETICS: N. F. WATERS PROC. N. A. S. and genetical behavior of this form is not incompatible with the segmental interchange theory of circle formation in Oenothera. Summary.-It is impossible for the
More informationGrowth and Development. Embryonic development 2/22/2018. Timing of hatching. Hatching. Young birds and their parents
Growth and Development Young birds and their parents Embryonic development From fertilization to hatching, the embryo undergoes sequence of 42 distinct developmental stages The first 33 stages vary little
More informationCitation for published version (APA): Prop, J. (2004). Food finding: On the trail to successful reproduction in migratory geese. Groningen: s.n.
University of Groningen Food finding Prop, Jouke IMPORTANT NOTE: You are advised to consult the publisher's version (publisher's PDF) if you wish to cite from it. Please check the document version below.
More informationComparative Physiology 2007 Second Midterm Exam. 1) 8 pts. 2) 14 pts. 3) 12 pts. 4) 17 pts. 5) 10 pts. 6) 8 pts. 7) 12 pts. 8) 10 pts. 9) 9 pts.
Name: Comparative Physiology 2007 Second Midterm Exam 1) 8 pts 2) 14 pts 3) 12 pts 4) 17 pts 5) 10 pts 6) 8 pts 7) 12 pts 8) 10 pts 9) 9 pts Total 1. Cells I and II, shown below, are found in the gills
More informationAlien egg retrieval in common pochard: Do females discriminate between conspecific and heterospecific eggs?
Ann. Zool. Fennici 46: 165 170 ISSN 0003-455X (print), ISSN 1797-2450 (online) Helsinki 30 June 2009 Finnish Zoological and Botanical Publishing Board 2009 Alien egg retrieval in common pochard: Do females
More informationRecall: The Earliest Thoughts about Flying Took place before the days of science.
Recall: The Earliest Thoughts about Flying Took place before the days of science. Before man began to investigate with carefully planned experiments, and to figure things out in an orderly fashion. Men
More informationSwan & Goose IDentification It s Important to Know
Swan & Goose IDentification It s Important to Know Reports from wildlife watchers and sportsmen will help the biologists monitor the recovery of trumpeter swans (Cygnus buccinator). Positive identification
More informationEVOLUTIONARY GENETICS (Genome 453) Midterm Exam Name KEY
PLEASE: Put your name on every page and SHOW YOUR WORK. Also, lots of space is provided, but you do not have to fill it all! Note that the details of these problems are fictional, for exam purposes only.
More informationTravel schedules to the high arctic: barnacle geese trade-off the timing of migration with accumulation of fat deposits
OIKOS 103: 403 414, 2003 Travel schedules to the high arctic: barnacle geese trade-off the timing of migration with accumulation of fat deposits Jouke Prop, Jeffrey M. Black and Paul Shimmings Prop, J.,
More informationAnhinga anhinga (Anhinga or Snake-bird)
Anhinga anhinga (Anhinga or Snake-bird) Family Anhingidae (Anhingas and Darters) Order: Pelecaniformes (Pelicans and Allied Waterbirds) Class: Aves (Birds) Fig. 1. Anhinga, Anhinga anhinga. [http://animaldiversity.ummz.umich.edu/accounts/anhinga_anhinga/,
More informationRapid City, South Dakota Waterfowl Management Plan March 25, 2009
Waterfowl Management Plan March 25, 2009 A. General Overview of Waterfowl Management Plan The waterfowl management plan outlines methods to reduce the total number of waterfowl (wild and domestic) that
More informationHawks Order Falconiformes
Hawks Hawks are grouped into four basic types depending on their physical features and food preferences: accipiters, buteos, falcons and harriers. In nature, when different species react to competition
More informationModeling and Control of Trawl Systems
Modeling and Control of Trawl Systems Karl-Johan Reite, SINTEF Fisheries and Aquaculture Supervisor: Professor A. J. Sørensen * Advisor: Professor H. Ellingsen * * Norwegian University of Science and Technology
More informationNo evidence for sex bias in winter inter-site movements in an Arcticnesting
Ibis (2015), 157, 401 405 Short communication No evidence for sex bias in winter inter-site movements in an Arcticnesting goose population MITCH D. WEEGMAN, 1,2 * ANTHONY D. FOX, 3 STUART BEARHOP, 1 GEOFF
More informationWWT/JNCC/SNH Goose & Swan Monitoring Programme survey results 2015/16
WWT/JNCC/SNH Goose & Swan Monitoring Programme survey results 2015/16 Pink-footed Goose Anser brachyrhynchus 1. Abundance The 56th consecutive Icelandic-breeding Goose Census took place during autumn and
More informationAdjustments In Parental Care By The European Starling (Sturnus Vulgaris): The Effect Of Female Condition
Proceedings of The National Conference on Undergraduate Research (NCUR) 2003 University of Utah, Salt Lake City, Utah March 13-15, 2003 Adjustments In Parental Care By The European Starling (Sturnus Vulgaris):
More informationFlight patterns of the European bustards
Flight patterns of the European bustards By Vhilip J. Stead THE BUSTARDS, as a family, are terrestial birds and spend the major part of their time on the ground, but both the Great Bustard Otis tarda and
More informationANALYSIS OF GROWTH OF THE RED-TAILED HAWK 1
OhioJ. Sci. DEVONIAN ICROPHYTOPLANKTON 13 Copyright 1983 Ohio Acad. Sci. OO3O-O95O/83/OOO1-OO13 $2.00/0 ANALYSIS O GROWTH O THE RED-TAILED HAWK 1 ARK A. SPRINGER 2 and DAVID R. OSBORNE, Department of Zoology,
More informationGiant Canada Goose, Branta canadensis maxima, in Arizona
Giant Canada Goose, Branta canadensis maxima, in Arizona Pierre Deviche (deviche@asu.edu) In 2004 the American Ornithologist s Union officially split North American Whitecheeked Geese into two species:
More informationENERGY BALANCE OF TRUMPETER SWANS AT STOPOVER AREAS DURING SPRING MIGRATION
NORTHWESTERN NATURALIST 85:104 110 WINTER 2004 ENERGY BALANCE OF TRUMPETER SWANS AT STOPOVER AREAS DURING SPRING MIGRATION JALENE MLAMONTAGNE 1,ROBERT MR BARCLAY, AND LELAND JJACKSON Ecology Division,
More informationResponse to SERO sea turtle density analysis from 2007 aerial surveys of the eastern Gulf of Mexico: June 9, 2009
Response to SERO sea turtle density analysis from 27 aerial surveys of the eastern Gulf of Mexico: June 9, 29 Lance P. Garrison Protected Species and Biodiversity Division Southeast Fisheries Science Center
More informationThe energetic cost of variations in wing span and wing asymmetry in the zebra finch Taeniopygia guttata
The Journal of Experimental Biology 27, 3977-3984 Published by The Company of Biologists 24 doi:1.1242/jeb.1235 3977 The energetic cost of variations in wing span and wing asymmetry in the zebra finch
More informationBROOD REDUCTION IN THE CURVE-BILLED THRASHER By ROBERTE.RICKLEFS
Nov., 1965 505 BROOD REDUCTION IN THE CURVE-BILLED THRASHER By ROBERTE.RICKLEFS Lack ( 1954; 40-41) has pointed out that in species of birds which have asynchronous hatching, brood size may be adjusted
More informationEgyptian vulture (Neophron percnopterus) research & monitoring Breeding Season Report- Beypazarı, Turkey
Egyptian vulture (Neophron percnopterus) research & monitoring - 2011 Breeding Season Report- Beypazarı, Turkey October 2011 1 Cover photograph: Egyptian vulture landing in Beypazarı dump site, photographed
More informationI. Introduction. Orientation and Navigation 3/8/2012. Most difficult problem Must know. How birds find their way. Two terms often misused
Orientation and Navigation How birds find their way I. Introduction Most difficult problem Must know Where it is Direction of goal Two terms often misused Orientation Navigation Orientation identify compass
More informationKing penguin brooding and defending a sub-antarctic skua chick
King penguin brooding and defending a sub-antarctic skua chick W. Chris Oosthuizen 1 and P. J. Nico de Bruyn 1 (1) Department of Zoology and Entomology, Mammal Research Institute, University of Pretoria,
More informationVigilance Behaviour in Barnacle Geese
ASAB Video Practical Vigilance Behaviour in Barnacle Geese Introduction All the barnacle geese (Branta leucopsis) in the world spend the winter in western Europe. Nearly one third of them overwinter in
More informationContrasting Response to Predator and Brood Parasite Signals in the Song Sparrow (melospiza melodia)
Luke Campillo and Aaron Claus IBS Animal Behavior Prof. Wisenden 6/25/2009 Contrasting Response to Predator and Brood Parasite Signals in the Song Sparrow (melospiza melodia) Abstract: The Song Sparrow
More informationAutumn staging behaviour in Pink-footed Geese; a similar contribution among sexes in parental care
Faculty of Biosciences, Fisheries and Economics Department of Arctic and Marine Biology Autumn staging behaviour in Pink-footed Geese; a similar contribution among sexes in parental care Henrik Langseth
More informationPROBABLE NON-BREEDERS AMONG FEMALE BLUE GROUSE
Condor, 81:78-82 0 The Cooper Ornithological Society 1979 PROBABLE NON-BREEDERS AMONG FEMALE BLUE GROUSE SUSAN J. HANNON AND FRED C. ZWICKEL Parallel studies on increasing (Zwickel 1972) and decreasing
More informationRed-Tailed Hawk Buteo jamaicensis
Red-Tailed Hawk Buteo jamaicensis This large, dark headed, broad-shouldered hawk is one of the most common and widespread hawks in North America. The Red-tailed hawk belongs to the genus (family) Buteo,
More informationNATURAL AND SEXUAL VARIATION
NATURAL AND SEXUAL VARIATION Edward H. Burtt, Jr. Department of Zoology Ohio Wesleyan University Delaware, OH 43015 INTRODUCTION The Darwinian concept of evolution via natural selection is based on three
More informationMigration. Migration = a form of dispersal which involves movement away from and subsequent return to the same location, typically on an annual basis.
Migration Migration = a form of dispersal which involves movement away from and subsequent return to the same location, typically on an annual basis. To migrate long distance animals must navigate through
More informationWinning with warts? A threat posture suggests a function for caruncles in Ross s Geese
Winning with warts? A threat posture suggests a function for caruncles in Ross s Geese m. r o b e r t McLa n d r e s s Introduction Agonistic behaviour in geese has been described by num erous investigators
More informationWaterfowl Along the Road
Waterfowl Along the Road Grade Level Third to Sixth Subject Areas Identification & Classification Bird Watching Content Standards Duration 20 minute Visitor Center Investigation Field Trip: 45 minutes
More informationEGG SIZE AND LAYING SEQUENCE
SEX RATIOS OF RED-WINGED BLACKBIRDS BY EGG SIZE AND LAYING SEQUENCE PATRICK J. WEATHERHEAD Department of Biology, Carleton University, Ottawa, Ontario KIS 5B6, Canada ABSTRACT.--Egg sex, size, and laying
More informationIntraspecific relationships extra questions and answers (Extension material for Level 3 Biology Study Guide, ISBN , page 153)
i Intraspecific relationships extra questions and answers (Extension material for Level 3 Biology Study Guide, ISBN 978-1-927194-58-4, page 153) Activity 9: Intraspecific relationships extra questions
More informationBreeding Activity Peak Period Range Duration (days) Laying May May 2 to 26. Incubation Early May to mid June Early May to mid June 30 to 34
Snowy Owl Bubo scandiacus 1. INTRODUCTION s have a circumpolar distribution, breeding in Fennoscandia, Arctic Russia, Alaska, northern Canada and northeast Greenland. They are highly nomadic and may migrate
More informationMallard and Blue-winged Teal Philopatry in Northwest Wisconsin
Mallard and Blue-winged Teal Philopatry in Northwest Wisconsin James O. Evrard Department 'of Natural Resources Box 367' Grantsburg, Wl 54840 ABSTRACT This study reports on the breeding and natal philopatry,
More informationPopulation Study of Canada Geese of Jackson Hole
National Park Service Research Center Annual Report Volume 4 4th Annual Report, 1980 Article 15 1-1-1980 Population Study of Canada Geese of Jackson Hole Gary Radke David Krementz Kenneth L. Diem Follow
More informationExercise 4: Animal Adaptations
Exercise 4: Animal Adaptations Introduction There are approximately 1.5 million species of organisms that have been described and named today. But, some scientists estimate that we may have as many as
More informationNaturalised Goose 2000
Naturalised Goose 2000 Title Naturalised Goose 2000 Description and Summary of Results The Canada Goose Branta canadensis was first introduced into Britain to the waterfowl collection of Charles II in
More informationSVALBARD PINK-FOOTED GOOSE
SVALBARD PINK-FOOTED GOOSE Population Status Report 2012-2013 Technical Report from DCE Danish Centre for Environment and Energy No. 29 2013 AU AARHUS UNIVERSITY DCE DANISH CENTRE FOR ENVIRONMENT AND ENERGY
More informationCo-operative breeding by Long-tailed Tits
Co-operative breeding by Long-tailed Tits v N. W. Glen and C. M. Perrins For most of this century, ornithologists have tended to believe that the majority of birds breed monogamously, with either the pair
More informationSwans & Geese. Order Anseriformes Family Anserinae
Swans & Geese Order Anseriformes Family Anserinae Swans and geese are large waterfowl most often seen in Pennsylvania during fall and spring migrations. They will stop to feed and rest on our state s lakes
More informationBean Goose a Yukon first at Whitehorse
15 Bean Goose a Yukon first at Whitehorse By Cameron D. Eckert On the morning of Saturday October 23, 1999 I received a call from Marten Berkman that a goose, possibly a Brant Branta bernicla, had been
More information8/19/2013. Topic 14: Body support & locomotion. What structures are used for locomotion? What structures are used for locomotion?
Topic 4: Body support & locomotion What are components of locomotion? What structures are used for locomotion? How does locomotion happen? Forces Lever systems What is the difference between performance
More informationBroad-winged Hawk. Visual identification tips. Other flight silhouettes
Rough-legged Hawk L = 21 in., WS = 53 in. Wt. = 2.2 lb. Pale chest and head Relatively small bill Feathered legs and small feet Habitat Open country, fields and marshes, nests on Arctic tundra Behavior
More informationNotes and Discussion
Am. Midl. Nat. 163:247 253 Notes and Discussion Hatching Chronology of Ducks using Playas in the Southern High Plains of Texas ABSTRACT. Breeding pair and brood surveys suggest that duck production in
More informationSurvivorship. Demography and Populations. Avian life history patterns. Extremes of avian life history patterns
Demography and Populations Survivorship Demography is the study of fecundity and survival Four critical variables Age of first breeding Number of young fledged each year Juvenile survival Adult survival
More informationThe Kongsfjorden colony of barnacle geese: Nest distribution and the use of breeding islands
The Kongsfjorden colony of barnacle geese: Nest distribution and the use of breeding islands 198-1997 INGUNN M. TOMBRE, FRIDTJOF MEHLUM and MAARTEN J. J. E. LOONEN Tombre, I. M., Mehium, F. & Loonen, M.
More informationThe effect of weaning weight on subsequent lamb growth rates
Proceedings of the New Zealand Grassland Association 62: 75 79 (2000) 75 The effect of weaning weight on subsequent lamb growth rates T.J. FRASER and D.J. SAVILLE AgResearch, PO Box 60, Lincoln, Canterbury
More information00:14 What would it feel like to fly like a bird? 00:21 To soar on feathered wings to faraway lands.
1 EARTHFLIGHT GIANT SCREEN RECORDED SCRIPT 00:14 What would it feel like to fly like a bird? 00:21 To soar on feathered wings to faraway lands. 00:27 Or defy gravity and effortlessly float on air 00:38
More informationMorphometrics and Flight Performance of Southern African Peregrine and Lanner Falcons
Morphometrics and Flight Performance of Southern African Peregrine and Lanner Falcons Andrew R. Jenkins Journal of Avian Biology, Vol. 26, No. 1. (Mar., 1995), pp. 49-58. http://links.jstor.org/sici?sici=0908-8857%28199503%2926%3a1%3c49%3amafpos%3e2.0.co%3b2-i
More informationStudies on the effects of disturbances on staging Brent Geese: a progress report
Studies on the effects of disturbances on staging Brent Geese: a progress report Martin Stock Stock, M. 1993. Studies on the effects of disturbances on staging Brent Geese: a progress report. Wader Study
More informationThe critical importance of incubation temperature
The critical importance of incubation temperature Nick A. French AVIAN BIOLOGY RESEARCH 2 (1/2), 2009 55 59 Aviagen Turkeys Ltd, Chowley Five, Chowley Oak Business Park, Tattenhall, Cheshire, CH3 9GA,
More informationBiol 160: Lab 7. Modeling Evolution
Name: Modeling Evolution OBJECTIVES Help you develop an understanding of important factors that affect evolution of a species. Demonstrate important biological and environmental selection factors that
More informationGPS in pigeon racing Denmark 2017 Kasper Korndal-Henriksen Ove Fuglsang Jensen
GPS in pigeon racing Denmark 2017 Kasper Korndal-Henriksen Ove Fuglsang Jensen BrevdueNord.dk Side 1 The team of GPS We are two fanciers in the team: Kasper K. Henriksen and Ove F. Jensen. Kasper has bought
More informationCitation for published version (APA): van der Graaf, A. J. (2006). Geese on a green wave: Flexible migrants in a changing world. s.n.
University of Groningen Geese on a green wave van der Graaf, Alexandra Johanna IMPORTANT NOTE: You are advised to consult the publisher's version (publisher's PDF) if you wish to cite from it. Please check
More informationShe is best known for her Newbery Medal-winning novel for young adults, Hitty, Her First Hundred Years, published in 1929.
Something Told the Wild Geese by Rachel Field. Print. Read the poem, Color the pictures. p.1. Something Told The Wild Geese Something told the wild geese It was time to go, Though the fields lay golden
More informationSPACING PATTERNS, MATING SYSTEMS, AND WINTER PHILOPATRY IN HARLEQUIN DUCKS
The Auk 117(2):299 307, 2000 SPACING PATTERNS, MATING SYSTEMS, AND WINTER PHILOPATRY IN HARLEQUIN DUCKS GREGORY J. ROBERTSON, 1,3 FRED COOKE, 1 R. IAN GOUDIE, 2,4 AND W. SEAN BOYD 2 1 Department of Biological
More informationVERTEBRATE READING. Fishes
VERTEBRATE READING Fishes The first vertebrates to become a widespread, predominant life form on earth were fishes. Prior to this, only invertebrates, such as mollusks, worms and squid-like animals, would
More information7. IMPROVING LAMB SURVIVAL
7. IMPROVING LAMB SURVIVAL Introduction It is widely accepted that there is a large amount of lamb wastage in Merino flocks. Fertility rates, as measured by the number of lambs present at scanning are
More informationDivergence in timing of parental care and migration in barnacle geese
Behavioral Ecology doi:10.1093/beheco/arq208 Advance Access publication 21 January 2011 Original Article Divergence in timing of parental care and migration in barnacle geese Rudy M. Jonker, a Marije W.
More informationTIME BUDGET OF BREEDING NORTHERN SHOVELERS
Wilson Bull., 91(l), 1979, pp. 42-49 TIME BUDGET OF BREEDING NORTHERN SHOVELERS ALAN D. AFTON McKinney (1970) suggested that the plankton-straining habits of Northern Shovelers (Areas clypeata) might require
More informationFemale Persistency Post-Peak - Managing Fertility and Production
May 2013 Female Persistency Post-Peak - Managing Fertility and Production Michael Longley, Global Technical Transfer Manager Summary Introduction Chick numbers are most often reduced during the period
More informationDoes begging affect growth in nestling tree swallows, Tachycineta bicolor?
Behav Ecol Sociobiol (2003) 54:573 577 DOI 10.1007/s00265-003-0668-2 ORIGINAL ARTICLE Marty L. Leonard Andrew G. Horn Jackie Porter Does begging affect growth in nestling tree swallows, Tachycineta bicolor?
More informationTrawls - Design, Construction and Methods
Trawls - Design, Construction and Methods Shri K.K. Kunjipalu Sr. Scientist The name trawl is derived from the manner of operating the net. The net is a off large bag net, tapering from the mouth forming
More informationEffects of Natural Selection
Effects of Natural Selection Lesson Plan for Secondary Science Teachers Created by Christine Taylor And Mark Urban University of Connecticut Department of Ecology and Evolutionary Biology Funded by the
More informationMoult, flight performance and wingbeat kinematics during take-off in European starlings Sturnus ulgaris
JOURNAL OF AVIAN BIOLOGY 34: 371 378, 2003 Moult, flight performance and wingbeat kinematics during take-off in European starlings Sturnus ulgaris Emma V. Williams and John P. Swaddle Williams, E. V. and
More informationCLADISTICS Student Packet SUMMARY Phylogeny Phylogenetic trees/cladograms
CLADISTICS Student Packet SUMMARY PHYLOGENETIC TREES AND CLADOGRAMS ARE MODELS OF EVOLUTIONARY HISTORY THAT CAN BE TESTED Phylogeny is the history of descent of organisms from their common ancestor. Phylogenetic
More informationRELATIONSHIPS AMONG WEIGHTS AND CALVING PERFORMANCE OF HEIFERS IN A HERD OF UNSELECTED CATTLE
RELATIONSHIPS AMONG WEIGHTS AND CALVING PERFORMANCE OF HEIFERS IN A HERD OF UNSELECTED CATTLE T. C. NELSEN, R. E. SHORT, J. J. URICK and W. L. REYNOLDS1, USA SUMMARY Two important traits of a productive
More informationStudies of less familiar birds 123. Glaucous Gull
Studies of less familiar birds 123. Glaucous Gull Photographs by W, PuchalsM (Plates J 9-42) AN EDITORIAL COMMENT with the photographs and paper by Kay (1947) on the characters of the Glaucous Gull (Larus
More informationINTER-FAMILY DOMINANCE IN CANADA GEESE
INTER-FAMILY DOMINANCE IN CANADA GEESE BY HAROLD C. HANSON SEVERAL factors combine to make the social habits of geese among the most interesting and complex in bird life: the slowness with which individuals
More information6. The lifetime Darwinian fitness of one organism is greater than that of another organism if: A. it lives longer than the other B. it is able to outc
1. The money in the kingdom of Florin consists of bills with the value written on the front, and pictures of members of the royal family on the back. To test the hypothesis that all of the Florinese $5
More informationThe Secret Life of Birds
The Secret Life of Birds Revealed Marilyn Ellis, OMN, CIG Oregon Master Naturalist Certified Interpretive Guide You can be a birdwatcher without. 1. Knowing what species they are by name OR 2. Recognizing
More informationIntegrated Management of Invasive Geese Populations in an International Context: a Case Study
Integrated Management of Invasive Geese Populations in an International Context: a Case Study Tim Adriaens, Frank Huysentruyt, Sander Devisscher, Koen Devos & Jim Casaer Neobiota 2014 4/11/2014, Antalya
More informationRepresentation, Visualization and Querying of Sea Turtle Migrations Using the MLPQ Constraint Database System
Representation, Visualization and Querying of Sea Turtle Migrations Using the MLPQ Constraint Database System SEMERE WOLDEMARIAM and PETER Z. REVESZ Department of Computer Science and Engineering University
More informationUniversity of Groningen
University of Groningen No sexual differences in embryonic period in jackdaws Corvus monedula and black-headed gulls Larus ridibundus Salomons, Henri; Mueller, Wendt; Dijkstra, C; Eising, Corine; Verhulst,
More informationThe Origin of Species: Lizards in an Evolutionary Tree
The Origin of Species: Lizards in an Evolutionary Tree NAME DATE This handout supplements the short film The Origin of Species: Lizards in an Evolutionary Tree. 1. Puerto Rico, Cuba, Jamaica, and Hispaniola
More informationAGE OF ONSET OF PUBERTY IN MERINO EWES IN SEMI-ARID TROPICAL QUEENSLAND
Proc. Aust. Soc. Anim. Prod. (1972) 9: 181 AGE OF ONSET OF PUBERTY IN MERINO EWES IN SEMI-ARID TROPICAL QUEENSLAND R. M. MURRAY* Summary TWO groups, each of 25 ewes were run with harnessed vasectomized
More informationIdentification. Waterfowl. The Shores of Long Bayou
Identification of Waterfowl at The Shores of Long Bayou Ernie Franke eafranke@tampabay.rr.com April 2015 Easy Identification of the Waterfowl Many Birds Look Alike: Great Blue Heron and Tri-Colored (Louisiana)
More informationOsprey Watch Osprey Monitoring Guidelines
Osprey Watch Osprey Monitoring Guidelines Here are the guidelines for volunteering to be a member of Greenbelt s Osprey Watch! Below you will find methodology explained, tips, and other informational facts
More informationBreeding success of Greylag Geese on the Outer Hebrides, September 2016
Breeding success of Greylag Geese on the Outer Hebrides, September 2016 Wildfowl & Wetlands Trust Report Author Carl Mitchell September 2016 The Wildfowl & Wetlands Trust All rights reserved. No part of
More information4B: The Pheasant Case: Handout. Case Three Ring-Necked Pheasants. Case materials: Case assignment
4B: The Pheasant Case: Handout Case Three Ring-Necked Pheasants As you can see, the male ring-necked pheasant is brightly colored. The white ring at the base of the red and green head stand out against
More informationCrotophaga major (Greater Ani)
Crotophaga major (Greater Ani) Family: Cuculidae (Cuckoos and Anis) Order: Cuculiformes (Cuckoos, Anis and Turacos) Class: Aves (Birds) Fig. 1. Greater ani, Crotophaga major. [http://www.birdforum.net/opus/greater_ani,
More informationBald Eagles in the Yukon. Wildlife in our backyard
Bald Eagles in the Yukon Wildlife in our backyard The Bald Eagle at a glance Both male and female adult Bald Eagles have a dark brown body and wings with a white head, neck and tail. They have a yellow
More informationFemale Persistency Post-Peak - Managing Fertility and Production
Female Persistency Post-Peak - Managing Fertility and Production Michael Longley, Global Technical Transfer Manager May 2013 SUMMARY Introduction Chick numbers are most often reduced during the period
More informationTHE HOLLINGWORTH GREENLAND WHITE-FRONTED GEESE
THE HOLLINGWORTH GREENLAND WHITE-FRONTED GEESE AN OVERVIEW OF THEIR REMARKABLE SAGA by Simon Hitchen and Ian McKerchar (Photo by Simon Hitchen) White-fronted Goose has always maintained a very scarce status
More informationLab 7. Evolution Lab. Name: General Introduction:
Lab 7 Name: Evolution Lab OBJECTIVES: Help you develop an understanding of important factors that affect evolution of a species. Demonstrate important biological and environmental selection factors that
More informationTesting the Ideal Free Distribution on Turtles in the Field
Testing the Ideal Free Distribution on Turtles in the Field Justin Carasa Nicole Cinquino Christopher Contreras Santiago Londoño Michelle Ortiz Andrea Remiro Alexander Rodriguez Research in Ecology University
More informationANIMAL BEHAVIOR. Laboratory: a Manual to Accompany Biology. Saunders College Publishing: Philadelphia.
PRESENTED BY KEN Yasukawa at the 2007 ABS Annual Meeting Education Workshop Burlington VT ANIMAL BEHAVIOR Humans have always been interested in animals and how they behave because animals are a source
More informationBirds THE BODY. attract =to pull towards. avoid =to keep away from. backbone =the row of connected bones that go down the middle of your back
attract =to pull towards avoid =to keep away from backbone =the row of connected bones that go down the middle of your back beak = the hard, pointed mouth of a bird bore = to make a hole breeding season
More informationThe fall and the rise of the Swedish Peregrine Falcon population. Peter Lindberg
Peregrine Falcon Populations status and perspectives in the 21 st Century J. Sielicki & T. Mizera (editors) European Peregrine Falcon Working Group, Society for the Protection of Wild Animals Falcon www.falcoperegrinus.net,
More informationcooper s Hawk (Accipiter cooperii)
Cooper s Hawk cooper s Hawk (Accipiter cooperii) OVErViEw Cooper s Hawks are larger than Sharpshinned Hawks but almost identical in plumage and very similar in shape. Cooper s Hawks from the West are smaller
More information