School of Biology

Dr Will Cresswell
Reader

I have two major research interests: behavioural ecology of birds and conservation ecology of birds.

Behavioural Ecology

My interests in behavioural ecology centre mainly around understanding how animals manage their risk of predation and how predators then compensate themselves to maximise their chance of catching prey. I concentrate on studying how small birds such as blackbirds or redshanks avoid depredation by raptors such as sparrowhawks or peregrines. I am also interested in foraging behaviour and the conflict between the need to forage and scan for predators, transfer of foraging and predator information between individuals, nest predation, incubation and foraging energetics, interference competition, individual foraging specialisations and variation in competitive ability and pursuit-deterrent signalling. A particular current research interest is how we measure and determine the non-lethal effects of predation risk.

Research Group: Present and past members

1. Charline Couchoux (2011): Masters student studying the existence of personality in individual redshanks' anti-predation decisions.
    
2. Alex Sansom (2005 - 2009): NERC PhD student investigating the fitness consequences of anti-predation behaviour in individual redshank.
    
3. Johan Lind (2003 - 2005) : Post-doc research fellow studying inter-specific and intraspecific variation in vigilance, management of predation risk and the development of anti-predation behaviour.
    
4. Ross MacLeod (2005 - 2006): Post-doc investigating the relationship between mass in birds and fitness using BTO ringing data.
    
5. John Quinn (2001 - 2004): Post-doc research fellow studying individual management of predation risk and hunting behaviour in raptors, based at the EGI, Oxford (Leverhulme Trust)

Conservation Ecology

My interests in conservation ecology centre mainly on the factors determining the density and distribution of endemic, declining and migrant birds. Much of this is based in West Africa and associated with the AP Leventis Ornithological Research Institute in Jos, Nigeria (APLORI www.aplori.org ) . I collect baseline survey and habitat association data necessary to formulate conservation strategies for endangered and declining birds. I also am interested in the effects of forest fragmentation on African birds, survival rates of tropical birds, differences in the foraging/predation trade-off between tropical and temperate birds and the use of degraded and farmland habitats by African birds and Palearctic migrant species.

Research Group: Present and past members

(Mainly funded by the Leventis Conservation Foundation but also other BirdLife sponsors)

1. Emma Blackburn (2011 – present):  PhD student studying factors determining the density and distribution of Palearctic migrants wintering in West Africa, using a bottom up individual based approach.
    
2. Sam Ivande (2011 – present):  PhD student studying factors determining the density and distribution of Palearctic migrants wintering in West Africa, using a top down, landscape and habitat selection approach.
    
3. Tamara Davies (2010 – present): PhD student studying the link between biodiversity and sustainability: a case study in the Solomon Islands.
    
4. Jenny Thomas (2010): Masters student examining the effects of fragmentation on bird communities in the long term very highly fragmented environment of Fife, Scotland.
    
5. Daniel Cox (2009 - present): PhD student studying how seasonality impacts on the life history of tropical birds.
    
6. Marina Xenophontos (2008 - present) : PhD student studying the effects of climate and habitat change on restricted range species: a case study of the endemic Cyprus Wheatear.
    
7. Tim Jones (2008) : Masters student examining how the phenology mismatch hypothesis (as a consequence of climate change) might account for migrant bird declines.
    
8. Shiiwua Manu (2003 - 2008): Post-doc research fellow studying the effects of forest fragmentation on bird biodiversity and also the foraging ecology of African birds
    
9. Matthew Stevens (2006 - 2010): PhD student studying the survial and other life history aspects of tropical birds.
    
10. Miriam Brandt (2004 - 2007): PhD student studying the competitive interactions that lead to ecological separation in closely related seedeaters, with particular emphasis on the endemic Rock Firefinch
     
11. Mark Hulme (2003 - 2007): PhD student studying the use of farmland by West African bird species
     
12. Ross McGregor (2001 - 2006) : PhD student studying the effects of seasonality on tropical birds and survival rates of tropical birds
     
13. Mark Watson (2004) : Post-doc studying the nest survival and breeding habitat requirements of the endangered Sociable Lapwing in Kazakstan
     
14. Jared Wilson (2001 - 2005): PhD student studying the factors determining the density and distribution of Palearctic migrants wintering in West Africa

Publications in international, citation indexed, peer reviewed journals:

Hulme, M. & Cresswell, W. (2012) Density and behaviour of Whinchats Saxicola rubetra on African farmland suggest that winter habitat conditions do not limit European breeding populations. Ibis in press.

Stevens, M.C., Ottosson, U., McGregor, R. & Brandt, M. & Cresswell, W. (2012) Survival rates in West African savannah birds. Ostrich in press.

Quinn, J.L. & Cresswell, W. (2012) Local prey vulnerability increases with multiple attacks by a predator. Oikos 121:1328-1334.

Quinn, J. L., Cole, E. F., Bates, J., Payne, R., & Cresswell, W. (2012) Personality predicts individual responsiveness to risk of starvation and predation. Proceedings of the Royal Society: Series B 279:1919-1926.

Couchoux, C. & Cresswell, W. (2012) Personality constraints versus flexible anti-predation behaviours: how important is boldness in risk management of redshanks (Tringa totanus) foraging in a natural system. Behavioral ecology 23:290-301.

Cox, D.T.C, Brandt, M.J., McGregor, R., Ottosson, U., Stevens, M.C. & Cresswell, W. (2011) Patterns of seasonal and yearly mass variation in West African tropical savannah birds. Ibis 153:672-683.

Cresswell, W. (2011) Predation in bird populations. Journal of Ornithology 152 (Suppl 1):S251-S263.

Lord, A.M, McCleery, R. & Cresswell, W. (2011) Incubation prior to clutch completion accelerates embryonic development and so hatch date for eggs laid earlier in a clutch in the Great tit, Parus major. Journal of Avian Biology 42: 187-191.

Cresswell, W. & Quinn, J.L. (2011) Predicting the optimal group-size from predator hunting behaviour. Journal of Animal Ecology 80: 310-319.

Wilson, J.M. & Cresswell , W. (2010) Densities of Palearctic warblers and Afrotropical species within the same guild in Sahelian West Africa. Ostrich 81:225-232.

Cresswell, W. & Quinn, J.L. (2010) Attack frequency, attack success and choice of prey group size for two predators with contrasting hunting strategies. Animal Behaviour 80: 643-648.

Manu, S., Imong, I.S. & Cresswell W. (2010) Bird species richness and diversity at montane IBA sites in South Eastern Nigeria. Bird Conservation International 20:231-239.

Wilson, J.M. & Cresswell , W. (2010) The Northern Wheatear Oenanthe oenanthe in the Sahel of West Africa: distribution, seasonal variation in abundance and habitat associations. Ostrich 81:115-121.

Stevens, M.C., Sheehan, D.K., Wilson, J.M., Buchanan, G.M. & Cresswell, W. (2010) Changes in Sahelian bird biodiversity and tree density over a five year period in Northern Nigeria. Bird Study 57:156-174.

Cresswell, W., Lind, J. & Quinn, J.L. (2010) Predator hunting success and prey vulnerability: quantifying the spatial scale over which lethal and non-lethal effects of predation occur. Journal of Animal Ecology 79:556-562.

Jones, T. & Cresswell, W. (2010) The phenology mismatch hypothesis: Are declines of migrant birds linked to uneven global change? Journal of Animal Ecology 79:98-108.

Sansom, A., Lind, J. & Cresswell, W. (2009) Individual behaviour and survival: the roles of predator avoidance, foraging success and vigilance. Behavioral Ecology 20:1168-1174.

Cresswell, W., Clark, J. & Macleod, R. (2009) How climate change might influence the starvation-predation risk trade-off response. Proceedings of the Royal Society: Series B 276: 3553-3560.

W. Cresswell, W., Butler, S., Whittingham, M.J. &  Quinn. J.L. (2009) Very short delays prior to escape from potential predators may function efficiently as adaptive risk-assessment periods. Behaviour 146:795-813.

Brandt, M.J. & Cresswell W. (2009) Diurnal foraging routines in a tropical bird, the rock finch Lagonosticta sanguinodorsalis: how important is predation risk? Journal of Avian Biology 40:90-94.

Macleod, R., Clark, J. & Cresswell, W. (2008) The starvation-predation risk trade-off, body mass and population status in the Common Starling Sturnus vulgaris. Ibis 150 S1:199-208.

Cresswell W. & Whitfield D.P. (2008) How starvation risk in Redshanks results in predation mortality from Sparrowhawks. Ibis 150 S1:209-218.

Brandt, M.J. & Cresswell W. (2008) Breeding behaviour, home range and habitat selection in Rock Firefinches (Lagonosticta sanguinodorsalis) in the wet and dry season in central Nigeria. Ibis 150:495-507.

Sansom, S., Cresswell W., Minderman, J. & Lind, L. (2008) Vigilance benefits and competition costs in groups: do individual redshanks gain an overall foraging benefit? Animal Behaviour 75:1869-1875.

Cresswell, W. (2008) Non-lethal effects of predation risk in birds. Ibis150:3-17.

Garcia-del-Rey, E., Cresswell, W., Perrins, C.M. & Gosler, A.G. (2007). Evolutionary trends and extreme cases of life history traits in the Blue Tit (Parus caeruleus) on oceanic islands (Canary Islands). Ardeola 54:27-39.

Garcia-del-Rey, E., & Cresswell, W.  (2007). The breeding biology of the endemic Berthelot’s Pipit Anthus berthelotii in a harsh oceanic island environment (Tenerife, Canary Islands). Ostrich 78:583-589.
 
MacLeod, R., Lind,J., Clark J., & Cresswell W. (2007) Mass regulation in response to predation risk can indicate population declines. Ecology Letters 10: 945-955.

McGregor, R., Whittingham, M.J. & Cresswell, W. (2007) Survival rates of tropical birds in Nigeria, West Africa. Ibis 149:615-618.

Cresswell, W., Wilson, J.M., Vickery J., Jones, P. & Holt, S. (2007) Changes in densities of Sahelian bird species in response to recent habitat degradation. Ostrich 78:247-253.

Wilson, J.M. & Cresswell, W. (2007) Identification of potentially competing Afrotropical and Palearctic bird species in the Sahel. Ostrich 78:363-368.

McGregor, R.M., Ottosson, U. & Cresswell W. (2007) Moult of guinea savanna passerines in West Africa. Ostrich 78:287-290.

Manu, S. & Cresswell W. (2007) Addressing sampling bias in counting forest birds: a West African case study. Ostrich 78:281-286.

Cresswell, W., Lind, J., Quinn, J.L., Minderman, J. & Whitfield, D.P.  (2007) Ringing or colour-banding does not increase predation mortality in redshanks. Journal of Avian Biology 38:309-316.

Manu, S., Peach, W. & Cresswell, W. (2007) The effects of fragment size and degree of isolation on avian species richness in highly fragmented forest in West Africa. Ibis 149:287-297.

Watson, M., Aebischer, N.J. & Cresswell W. (2007) Vigilance and fitness in grey partridges Perdix perdix: the effects of group size and foraging-vigilance trade-offs on predation mortality. Journal of Animal Ecology 76:211-221.

Quinn, J.L., Whittingham, M.J., Butler, S.J. & Cresswell, W. (2006) Noise, predation risk compensation and vigilance in the chaffinch Fringilla coelebs. Journal of Avian Biology 37:601-608.

Wilson, J.M. & Cresswell, W. (2006) How robust are Palearctic migrants to habitat loss and degradation in the Sahel? Ibis 148:789-800.

Quinn, J.L. & Cresswell, W. (2006) Testing domains of danger in the selfish herd: sparrowhawks target widely spaced redshanks in flocks. Proceedings of the Royal Society: Series B 273:2521-2526.

Watson M., Wilson J. M., Koshkin M., Sherbakov B., Karpov F., Gavrilov A., Schielzeth, H., Brombacher M., Collar N.J. & Cresswell W. (2006) Nest survival and productivity of the critically endangered Sociable Lapwing Vanellus gregarious. Ibis 148:489-502.

Garcia-del-Rey, E., Cresswell, W., Perrins, C. & Gosler, A. (2006) Variable effects of laying date on clutch size in the Canary Island Blue Tits (group). Ibis 148:564-567.   

Minderman, J., Lind, J. & Cresswell W. (2006) Behaviourally mediated indirect effects: Interference competition increases predation mortality in foraging redshanks. Journal of Animal Ecology 75:713-723.

Lind, J. & Cresswell, W. (2006) Anti-predation behaviour during bird migration; the benefit of studying multiple behavioural dimensions. Journal of Ornithology 147:310-316.

MacLeod R., Barnett P., Clark J., Cresswell W. (2006) Mass-dependent predation risk as a mechanism for house sparrow declines? Biology Letters 2:43-46.

Butler,S.J., Whittingham,M.J., Quinn,J.L. & Cresswell,W. (2006) Time in captivity and individual differences influence experimental success: foraging trials on wild-caught chaffinches. Behaviour 143: 535-548.

Garcia-del-Rey, E. & Cresswell, W. (2006) Population size and habitat selection of the Feurteventura Blue Tit (Parus caeruleus degener). Ostrich 77:105-108.

Garcia-del-Rey, E. & Cresswell, W. (2005) Density estimates, microhabitat selection, and foraging behaviour of the endemic blue chaffinch Fringilla teydae teydae on Tenerife (Canary Islands). Ardeola 52: 305-317.

Manu, S., Peach, W., Bowden, C. & Cresswell W. (2005) The effects of forest fragmentation on the population density and distribution of the globally endangered Ibadan Malimbe Malimbus ibadanensis. Bird Conservation International 15: 275-285.

Quinn, J.L. & Cresswell, W. (2005) Personality and anti-predation behaviour in the chaffinch Fringilla coelebs. Behaviour 142: 1383-1408.

MacLeod, R., Gosler, A. & Cresswell, W. (2005). Diurnal mass gain strategies and perceived predation risk in the great tit, Parus major. Journal of Animal Ecology 74:956-964.

Lind, J. & Cresswell, W. (2005). Determining the fitness consequences of anti-predation behaviour. Behavioral Ecology 16:945-956.

Quinn, J.L. & Cresswell, W. (2005) Escape response delays in wintering redshank Tringa totanus flocks are explained by the perceptual limit and economic hypotheses. Animal Behaviour 69:1285-1292.

Githiru, M., Lens, L. & Cresswell W. (2005) Nest predation in a fragmented Afrotropical forest: evidence from natural and artificial nests. Biological Conservation 123:189-196.

MacLeod, R., Barnett, R.B., Clark, J. & Cresswell, W. (2005) Body mass change strategies in blackbirds Turdus merula: the starvation-predation risk trade-off. Journal of Animal Ecology 74:292-302.

Butler,S.J., Whittingham,M.J., Quinn,J.L. & Cresswell,W. (2005) Quantifying the interaction between food density and habitat structure in determining patch selection. Animal Behaviour 69:337-343.

Whittingham,M.J., Butler,S.J., Quinn,J.L. & Cresswell,W. (2004) The effect of limited visibility on vigilance behaviour and speed of predator detection. Oikos 106:377-385.

Cresswell, W., Holt, S., Reid, J.M., Whitfield, D.P., Mellanby, R.J., Norton, D., & Waldron, S. (2004) The energetic costs of egg heating constrain incubation attendance but do not determine daily energy expenditure in the Pectoral Sandpiper. Behavioral Ecology 15:498-507.

Catry, P., Campos, A., Almada, V. & Cresswell, W. (2004) Winter segregation of migrant European Robins Erithacus rubecula in relation to sex, age and size. Journal of Avian Biology 35:204-209.

Quinn, J.L. & Cresswell, W. (2004). Predator hunting behaviour and prey vulnerability. Journal of Animal Ecology 73:143-154.

Cresswell, W. & Quinn, J. (2004). Faced with a choice, predators select the most vulnerable group: implications for both predators and prey for monitoring relative vulnerability. Oikos 104:71-76.

Yasué, M., Quinn, J.L. & Cresswell, W. (2003). Multiple effects of weather on the starvation and predation risk trade-off in choice of feeding location in redshanks. Functional Ecology 17:727-736.

Cresswell, W., Lind, J., Kaby, U., Quinn, J.L. & Jakobsson, S. (2003). Does an opportunistic predator preferentially attack non-vigilant prey? Animal Behaviour 66: 643-648.

Cresswell,W. (2003). Testing the mass-dependent predation hypothesis: in European blackbirds poor foragers have higher overwinter body reserves. Animal Behaviour 65:1035-1044.

Cresswell, W., Quinn, J.L., Whittingham, M.J., & Butler, S. (2003). Good foragers can also be good at detecting predators. Proceedings of the Royal Society: Series B 270:1069-1076.

Cresswell W. & McCleery, R. (2003) How great tits maintain synchronisation of their hatch date with food supply in response to long term variability in temperature. Journal of Animal Ecology 72:356-366.

Cresswell, W., Holt, S., Reid, J.M., Whitfield, D.P. & Mellanby, R.J. (2003) Do the energetic demands of incubation constrain incubation scheduling in a biparental species. Behavioral Ecology 14:97-102.

Smith, R.D., Ruxton, G.D. & Cresswell, W. (2002) Do kleptoparasites reduce their own foraging effort in order to detect kleptoparasitic opportunities? An empirical test of a key assumption of kleptoparasitic models. Oikos 97: 205-212.

Reid, J.M., Cresswell, W., Holt, S., Mellanby, R.J., Whitfield, D.P. & Ruxton, G.D. (2002). Nest scrape design and clutch heat loss in Pectoral Sandpipers (Calidris melanotos). Functional Ecology 16:305-312.

McGowan, A., Cresswell, W. & Ruxton, G.D. (2002) The effects of daily weather variation on foraging and responsiveness to disturbance in overwintering Red Knot (Calidris canutus). Ardea 90:229-237.

Smith, R.D., Ruxton, G.D. & Cresswell, W. (2001) Patch choice decisions of wild blackbirds: the role of pre-harvest public information Animal Behaviour 61:1113-1124.

Smith, R.D., Ruxton, G.D. & Cresswell, W. (2001) Dominance and feeding interference in small groups of blackbirds Behavioral Ecology 12:475-481.

Cresswell, W. (2001). Relative competitive ability does not change over time in blackbirds. Journal of Animal Ecology 70:218-227.

Cresswell, W. , Smith, R.D. & Ruxton, G.D. (2001). Absolute foraging rate and susceptibility to interference competition in blackbirds varies with patch conditions. Journal of Animal Ecology 70:228-236.

Cresswell, W. Hilton, G.M.,& Ruxton, G.D. (2000) Evidence for a rule governing the avoidance of superfluous escape flights. Proceedings of the Royal Society: Series B 267:1069-1076.

Cresswell, W. (1999). Travel distance and mass gain in wintering blackbirds. Animal Behaviour 58:1109-1116.

Hilton, G.M., Ruxton, G.D. & Cresswell, W. (1999) Choice of foraging area with respect to predation risk in redshanks: the effects of weather and predator activity. Oikos 87:295-302.

Hilton, G.M., Cresswell, W. & Ruxton, G.D. (1999) Intra-flock variation in the speed of escape-flight response on attack by an avian predator. Behavioural Ecology 10: 391-395.

Whitfield D.P., Cresswell W., Ashmole N.P., Clark N.A. & Evans A.D. (1999) No evidence for Sparrowhawks selecting Redshanks according to size and condition. Journal of Avian Biology 30:31-39.

Cresswell, W., Yerokhov, S., Berezovikov, N., Mellanby, R., Bright, S., Catry, P., Chaves, J., Freile, J., Gretton, A., Zykin, A., McGregor, R. & McLaughlin, D. (1999). Important wetlands in northern and eastern Kazakstan. Wildfowl 50:181-194.

Vickery, J., Thomas D., Rowcliffe, M., Cresswell, W., Jones, P. & Holt, S. (1999) Habitat selection of whitethroats during spring passage in the Sahel zone of northern Nigeria. Bird Study 46: 348-355.

Cresswell, W., M. Hughes, R. Mellanby, S. Bright, P. Catry, J. Chaves, J. Freile, A. Gabela, H. Martineau, R. MacLeod, F. McPhee, N. Anderson, S. Holt, S. Barabas, C. Chapel & T. Sanchez (1999) Densities and habitat preferences of Andean cloud-forest birds in pristine and degraded habitats in northeastern Ecuador. Bird Conservation International 9:124-145.

Cresswell, W. (1998) Relative competitive ability changes with competitor density: evidence from foraging blackbirds. Animal Behaviour 56:1367-1373.

Cresswell, W. (1998) Variation in the strength of interference competition with resource density in blackbirds Turdus merula. Oikos 81:152-160.

Cresswell, W. (1998) Diurnal and seasonal mass variation in blackbirds Turdus merula: consequences for mass-dependent predation risk. Journal of Animal Ecology 67:78-90.

Cresswell, W. (1997) Interference competition at low competitor densities in blackbirds Turdus merula. Journal of Animal Ecology 66:461-471.

Cresswell, W. (1997) Nest predation rates and nest detectability at different stages of breeding in blackbirds Turdus merula. Journal of Avian Biology 28:296-302.

Cresswell, W. (1997) Nest predation: the relative effects of nest characteristics, clutch size and parental behaviour. Animal Behaviour 53:93-103.

Cresswell, W., Irwin, M., Jensen, M., Mee, A., Mellanby, R., McKean, M. & Milne, L. (1997) Population estimates and distribution changes of landbirds on Silhouette Island, Seychelles. Ostrich 68: 50-57.

Cresswell, W. (1996) Surprise as a winter hunting strategy in Sparrowhawks Accipiter nisus, Peregrines Falco peregrinus and Merlins F. columbarius. Ibis 138:684-692.

Jones, P., Vickery, J., Holt, S., & Cresswell, W. (1996) A preliminary assessment of some factors influencing the density and distribution of Palearctic passerine migrants wintering in the Sahel zone of West Africa. Bird Study 43:73-84.

Cresswell, W. (1995) Selection of avian prey by wintering sparrowhawks Accipiter nisus in southern Scotland. Ardea 83:381-389.

Cresswell, W. (1994) Age-dependent choice of redshank (Tringa totanus) feeding location: profitability or risk? Journal of Animal Ecology 63:589-600.

Cresswell, W. (1994) Flocking is an effective anti-predation strategy in Redshanks, Tringa totanus. Animal Behaviour 47: 433-442.

Cresswell, W. (1994) The function of alarm calls in redshanks, Tringa totanus. Animal Behaviour 47:736-738.

Cresswell, W. (1994) Song as a pursuit-deterrent signal, and its occurrence relative to other anti-predation behaviours of skylark (Alauda arvensis) on attack by merlins (Falco columbarius). Behavioural Ecology and Sociobiology 34:217-223.

Cresswell, W. & Whitfield, D.P. (1994) The effects of raptor predation on wintering wader populations at the Tyninghame estuary, southeast Scotland. Ibis 136:223-232.

Cresswell, W. (1993) Escape responses by redshanks, Tringa totanus, on attack by avian predators. Animal Behaviour 46:609-611.
 

Other peer reviewed publications:

Cresswell, W. (2010) Empirical studies of predator and prey behaviour. In Breed, M. D. & Moore, J., eds. Encyclopedia of Animal Behavior , pp 633-638. Oxford: Academic Press.

Cresswell, W., Boyd, M. & Stevens, M. (2009). Movements of Palearctic and Afrotropical bird species during the dry season (November–February) within Nigeria. pp. 18–28. In: Harebottle, D.M., Craig, A.J.F.K., Anderson, M.D., Rakotomanana, H. & Muchai. (eds). Proceedings of the 12th Pan African Ornithological Congress, 2008. Cape Town, Animal Demography Unit.

Cresswell, W. (2009) The use of mass and fat reserve measurements from ringing studies to assess body condition. Ringing & Migration 24: 227-232.

Manu, S., Peach, W. & Cresswell, W. (2005). Notes on the natural history of the Ibadan Malimbe Malimbus ibadanensis, a threatened Nigerian endemic. Malimbus 27:33-39.
Cresswell, W. (2004) Kleptoparasitism rates and aggressive interactions between raptors. In Raptors Worldwide: Proceedings of the 6th World Conference on Birds of Prey and Owls. Chancellor, R. D. & B.-U. Meyburg eds. pp 805 – 814.

Manu, S. & Cresswell, W. (2002). The effects of forest fragmentation on Palearctic migrants in south western Nigeria. In Wings Over Africa: Proceedings of the International Seminar on Bird Migration: Research, Conservation, Education and Flight Safety (Eds. Leshem, Y., Froneman, A., Mundy, P. Shamir, H.), pp 143 – 150. International Center for the Study of Bird Migration, Israel.

Cresswell, W., R. Mellanby, S. Bright, P. Catry, J. Chaves, J. Freile, A. Gabela, M. Hughes, H. Martineau, R. MacLeod, F. McPhee, , N. Anderson, S. Holt, S. Barabas, C. Chapel & T. Sanchez. (1999) Birds of the Guandera Reserve, Carchi province, northeastern Ecuador. Cotinga 11:55-63.

Cresswell, W. (1997). Carrion crows catching waders. British Birds 90:366.

Cresswell, W. (1997). Caching of prey by carrion crows. British Birds 90 366-367.