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Nest parasitism of Pochard Aythya ferina by Red‐crested Pochard Netta rufina
Abstract
Parasitic red-crested pochards apparently actively search for host nests within the preferred nesting habitat of the latter in the Donana National Park. Red-crested pochards mainly parasitise during the later stages of their nesting season, suggesting that parasites are young females or (more probably) that some females have lost their clutches and have subsequently become parasitic to minimise time. Mean clutch size of pochard was not reduced following nest parasitism. Although female pochard often ejected red-crested pochard eggs, there must be a net benefit to the latter when compared with non-parasitic late-season brooding.-P.J.Jarvis
... Anas platyrhynchos Marismas del Guadalquivir Coronado (1972); Amat (1991) La Mancha Coronado (1972) República Checa Kux (1963); Musil y Neužilová (2009) Lago de Thun (Suiza) Hauri (1989) Lago de Neuchâtel (Suiza) Keller (2014) Lolland (Dinamarca) Petersen (1943) Paises Bajos Voous (1947) Sidi Boughaba (Marruecos) Cherkaoi et al. (2013) Mareca strepera Marismas del Guadalquivir J. A. Amat (inédito) La Mancha Coronado (1972) Veluwemeer-Zuid (Países Bajos) Hellebreckers y Voous (1964) Spatula clypeata La Mancha Coronado (1972) Aythya ferina Marismas del Guadalquivir Coronado (1972); Amat (1985) Lolland (Dinamarca) Petersen (1943) Nakskov Indrefjord (Dinamarca) Löppenthin (1960) Aythya fuligula Lago de Thun (Suiza) Hauri (1989) Lago de Neuchâtel (Suiza) Keller (2014) En unas pocas ocasiones se han registrado nidos de ánade azulón parasitados simultáneamente por pato colorado y porrón europeo en las marismas del Guadalquivir (Coronado, 1972). ...
... de nidificación, ni en las fechas de puesta o tamaños de puesta del porrón europeo, entre nidos parasitados y no parasitados(Amat, 1985). El número medio de huevos de pato colorado en nidos de porrón europeo fue 2,5 ± 1,7 (n = 63). ...
... El número medio de huevos de pato colorado en nidos de porrón europeo fue 2,5 ± 1,7 (n = 63). El parasitismo de nidos supuso un coste para los porrones europeos, ya que el porcentaje de huevos de porrón arrojados fuera de los nidos fue significativamente mayor en nidos parasitados que en los no parasitados (10,8% vs. 3,5%); además, el porcentaje de huevos de porrón que no llegó a eclosionar en los nidos que tuvieron éxito fue mayor en nidos parasitados que en los no parasitados (17,6% vs. 9,3%), probablemente como consecuencia de las dificultades de incubar eficientemente un número mayor de huevos(Amat, 1985). ...
... Anas platyrhynchos Marismas del Guadalquivir Coronado (1972); Amat (1991) La Mancha Coronado (1972) República Checa Kux (1963); Musil y Neužilová (2009) Lago de Thun (Suiza) Hauri (1989) Lago de Neuchâtel (Suiza) Keller (2014) Lolland (Dinamarca) Petersen (1943) Paises Bajos Voous (1947) Sidi Boughaba (Marruecos) Cherkaoi et al. (2013) Mareca strepera Marismas del Guadalquivir J. A. Amat (inédito) La Mancha Coronado (1972) Veluwemeer-Zuid (Países Bajos) Hellebreckers y Voous (1964) Spatula clypeata La Mancha Coronado (1972) Aythya ferina Marismas del Guadalquivir Coronado (1972); Amat (1985) Lolland (Dinamarca) Petersen (1943) Nakskov Indrefjord (Dinamarca) Löppenthin (1960) Aythya fuligula Lago de Thun (Suiza) Hauri (1989) Lago de Neuchâtel (Suiza) Keller (2014) En unas pocas ocasiones se han registrado nidos de ánade azulón parasitados simultáneamente por pato colorado y porrón europeo en las marismas del Guadalquivir (Coronado, 1972). ...
... de nidificación, ni en las fechas de puesta o tamaños de puesta del porrón europeo, entre nidos parasitados y no parasitados(Amat, 1985). El número medio de huevos de pato colorado en nidos de porrón europeo fue 2,5 ± 1,7 (n = 63). ...
... El número medio de huevos de pato colorado en nidos de porrón europeo fue 2,5 ± 1,7 (n = 63). El parasitismo de nidos supuso un coste para los porrones europeos, ya que el porcentaje de huevos de porrón arrojados fuera de los nidos fue significativamente mayor en nidos parasitados que en los no parasitados (10,8% vs. 3,5%); además, el porcentaje de huevos de porrón que no llegó a eclosionar en los nidos que tuvieron éxito fue mayor en nidos parasitados que en los no parasitados (17,6% vs. 9,3%), probablemente como consecuencia de las dificultades de incubar eficientemente un número mayor de huevos(Amat, 1985). ...
... Individuals adopting alternative strategies usually initiate laying in the nests of other individuals, and after laying some eggs in such nests continue laying, in some cases almost without interruption, in their own nests (Weller 1959;Clawson et al. 1979;Hori 1987;Sorenson 1991). Individuals adopting conditional strategies usually parasitise nests of others when there is no possibility of initiating normal nesting; therefore such individuals would be making the 'best of a bad situation' (Amat 1985;Lank et al. 1989;Briggs 1991;Sorenson 1991;Lyon 1993). In the case of shorebirds, it has been suggested that, when females lose their nests to predators during the laying period, they may deposit the remainder of the clutch in nests of other shorebirds (Colwell 1986). ...
... The observations were made in the marshes of the Guadalquivir (3707 ' N, 6 ø 12' W) and Fuente de Piedra lake (3706 ' N, 4045 ' W). Descriptions of these sites may be found in Amat (1985) and Fraga & Amat (1996). ...
... Although clutch sizes larger than the mode which are attributable to two females laying in the same nest have been recorded in many shorebird species (Cramp & Simmons 1983), the frequency of occurrence of mixed clutches among shorebirds is very low (but see Giroux 1985), contrasting with other precocial species in which facultative nest parasitism is high (i.e. >20% of nests of the host species parasitized, Joyner 1976; Clawson et al. 1979;Amat 1985;Sorenson 1991;Lyon & Everding 1996). Thus, in this study only 1-5% of clutches contained eggs of more than one female. ...
Amat, J.A. 1998. Mixed clutches in shorebirds nests: why are they so uncommon? Wader Study Group Bull. 85: 55-59. Mixed clutches, in which two females deposit their eggs in the same nest, have been recorded in many shorebird species, but their frequency of occurrence is low in comparison with that of other precocial birds (e.g. ducks). This paper provides new observations of mixed clutches both between and within species, for Kentish Plover Charadrius alexandrinus, Black-winged Stilt Himantopus himantopus and Avocet Recurvirostra avosetta. I argue that mixed clutches are relatively uncommon among shorebirds because of a limitation in the parental ability to care for very small chicks when broods are large, rather than by a limitation in the ability to incubate large clutches.
... Those studies do not unanimously support the idea of no cost to host. Hosts may suffer lower nest success (McCamant and Bolen 1979, Haramis and Thompson 1985, Lank et al. 1990), clutch sizes (Andersson and Eriksson 1982), and hatching success (Amat 1985, Sorenson 1997. In contrast, others have suggested hosts benefit via increased offspring survival (Nudds 1980, Eadie andLumsden 1985). ...
... We detected no difference in clutch size, hatch success, or nest success between parasitized and nonparasitized females. Amat (1985) reported lower hatch success in Common Pochard nests parasitized by Red-crested Po-Effect of Brood Parasitism chards (Netta rufina). He attributed increased mortality to inefficient incubation of enlarged clutches, which resulted in more dead embryos. ...
Brood parasitism occurs disproportionately in birds with precocial young and is particularly common in Anseriformes. In part, that pattern may result because precocial hosts, relative to altricial species, incur relatively few costs when caring for precocial eggs. Empirical data do not consistently support that hypothesis, and some parameters have not been adequately compared between parasitized and nonparasitized nests or females. We used a combination of experimentation (egg and duckling additions) and analysis of a larger observational data set to compare reproductive parameters, recruitment, and adult survival between parasitized and nonparasitized female Common Pochard (Aythya ferina) and Tufted Ducks (A. fuligula). Addition of three eggs to nests during the host's laying cycle had no effect on host clutch size, host egg hatch success, or nest success for either species. Nest success was not affected by parasitism intensity for pochards, but we did detect a small drop in nest success for Tufted Duck nests parasitized with >6 eggs. Recruitment probability did not differ between parasitized and nonparasitized nests for either species, and parasitism had no negative effect on adult survival. Between-year nest initiation dates were later for parasitized Tufted Ducks, although the biological consequences of that difference (3.8 days) seem negligible. Moderate levels of parasitism do not negatively affect hosts for these two species.
... (Weller 1959), red-crested pochards, Netta refina (Amat 1985 ), and ruddy ducks, Oxyura jamaicensis (Joyner 1983). In other species, such as snow geese, Chen caerulescens (Lank et a!. ...
... A host-parasite relationship similar to that of canvasbacks and redheads is possible in another pair of diving ducks, the pochard, Aythya ferina, and red-crested pochard, but results from one area suggest some major differences. First, rates of interspecific parasitism were relatively high for both species: red-crested pochards parasitized 31% of pochard nests (Amat 1985) and 42% of mallard nests (Amat 1991), whereas pochards parasitized 18% of red-crested pochard nests (Amat 1993) and 5% of mallard nests (Amat 1991). Second, the earlier nesting species of the pair, the red-crested pochard (Amat 1982), also exhibited the higher frequency of parasitic egg laying. ...
This book is the first to present a comprehensive overview of parasitic birds and their hosts. Although the phenomenon has attracted the interest of naturalists and evolutionists since Darwin, only recently have researchers applied modern evolutionary theory and experimental methods to study the various adaptations related to brood parasitism. The work in this field is accelerating rapidly, and this volume collects work from the individuals and research groups around the world who have been responsible for nearly every major study in the last ten years. The papers present valuable summaries along with substantial new research, and the volume concludes with a review of important unsolved questions. The book is an invaluable resource on this fascinating topic, covering the remarkable sequences of adaptations and counter-adaptations, along with the perhaps even more remarkable cases where adaptations seem to be lacking.
... (2) Nests subjected to conspecific or interspecific brood parasitism may be more likely to be deserted by females on the basis that avian brood parasites decrease the fitness of their hosts by reducing their breeding success (Weller 1959;Payne 1977;Giroux 1981;Amat 1985). Contrary to expectations, there was no apparent association between breeding failure or clutch desertion and brood parasitism in our study. ...
The status of waterbirds breeding in protected areas in North Africa needs constant monitoring because of a naturally fluctuating environment and permissive attitudes towards illegal activities likely to negatively affect population dynamics of threatened species. We present the results of a study conducted at a protected site, Lake Tonga, north-eastern Algeria, on a breeding population of Ferruginous Duck Aythya nyroca, a Near-Threatened duck subjected to considerable pressure from egg-pilfering and illegal hunting. Two distinct habitats within the lake were used by Ferruginous Duck: an Alder carr (Alnus glutinosa) and floating islets across the lake. The mean clutch size was 9.51±1.84 eggs (N = 51 clutches) with hatching rate of 80.7% for successful clutches. Breeding success was low (37%) with predation (33%) and clutch desertion (17%) accounting for the majority of failed nests. The probabilities of nest failure and nest desertion increased with a delayed onset of egg laying. Predation was not significantly associated with egg laying date and vegetation cover, but late breeders nesting in dense vegetation seemed to suffer less predation. Conspecific brood parasitism was positively associated with nest size, whereas interspecific brood parasitism was marginally associated with water depth. We discuss different hypotheses concerning nest desertion, and argue that illegal hunting and disturbance may best explain why birds desert their nests.
The present ornithological report for the Camargue covers six years (1995-2000). This time-period was characterized by mild and wet winters (except the winter of 1999-2000 which was very dry but remained mild). The mean temperatures were all higher than those measured previously. Twenty-two new species have been recorded for the first time (their list is given in the introduction of this paper). The following rare species have been observed again: Blue-winged Teal (a ringed bird in Québec/Canada shows the wild origin of at least one of the three birds seen), Lesser Scaup, Ring-necked Duck, Eastern Imperial Eagle, Lanner Falcon, Saker Falcon, Purple Swamp-hen, Great Bustard, Black-winged Pratincole, Great Sand Plover, Sociable Lapwing, Purple Sandpiper, Buff-breasted Sandpiper, Wilson's Phalarope, Audouin's Gull, Arctic Tern, Common Guillemot, Blue-cheeked Bea-eater, Horned Lark, Richard's Pipit, Blyth's Pipit, Isabelline Wheatear, Desert Wheatear, Paddyfield Warbler, Marsh Warbler, Barred Warbler, Yellow-browed Warbler, Red-breasted Flycatcher, European Nuthatch, Rosy Starling, Snowfinch, Trumpeter Finch and Lapland Longspur. Among the species or group of species which are regularly censused, two arboreal herons (Little Egret and Cattle Egret) have dramatically increased their numbers; the 680 pairs of Night Heron and 266 pairs of Squacco Heron in 2000 must be outlined. The Grey Heron stopped its spectacular increase and the Purple Heron continued to fluctuate (1 370 nests in 1996 and 664 nests in 2000). The Greater Flamingo reached the very high figure of 22 200 pairs in 2000 (13 000 in 1996). The breeding gulls and terns in the salines showed some new trends: the Black-headed Gull dramatically decreased (but began to colonize freshwater breeding sites), the Mediterranean Gull reached the very high number of 1 877 pairs in 2000, the Slender-billed Gull maintained its high breeding number (850 pairs in 2000). The four tern species showed the usual fluctuations. The high number of breeding Yellow-legged Gull remained a concern. The salines at Salin-de-Giraud harboured most of the breeding population during this time-period whereas the salines at Aigues-Mortes lost most of their birds. The wintering ducks and coots continued their overall decrease considered as linked to excessive hunting pressure (mostly through disturbance effect of hunting on feeding grounds). The species that have been found breeding for the first time are the Great Cormorant (in 1998), the Great White Egret (first sucessful breeding in 1996), the Eurasian Spoonbill (in 1998), the Eagle Owl (in 2000) and the Pied Wagtail. Among the breeding species, the Collared Pratincole showed a good breeding success in 2000 (42 pairs and 45 fledglings) and several breeding records were found for the Great Spotted Cuckoo. Some species increasingly overwintered: Night Heron, Black Stork, White Stork, Black Kite, Osprey, Common Crane, Stone-curlew, Little Ringed Plover, Common Tern and Pine Bunting.
The Red-crested Pochard Netta rufina colonised Switzerland in the 20th century. In 1927 the first nest was found in the Swiss part of Lake Constance (Bodensee), ten years after the first breeding records on the German side. Until 1964, when the first brood was confirmed on Lake Zurich, breeding was restricted to Lake Constance. Until 1980 breeding records in Switzerland remained scarce but since then breeding has been confirmed every year. In the 1990s a rapid increase started, reaching 222 confirmed broods in 2011. The number of breeding pairs for this year was estimated at around 450. The increase happened in parallel to the massive increase in wintering numbers from a few hundred in the mid-1980s to a maximum of over 30 000 in 2009. Redcrested Pochards breed mainly on the large lakes of the Swiss plateau, with the highest numbers on sites where wintering birds concentrate. Apart from isolated records on Lac de Joux at 1000 m a.s.l., breeding is restricted to lowland areas (below 600 m). Lake Neuchâtel, leading the list of the most important wintering sites together with Lake Constance, holds around half of the Swiss breeding population. In the last decade, the species has increasingly spread to small waterbodies. Data collected by volunteers give an insight into the breeding biology, although no systematic sampling has taken place. The Red-crested Pochard has a long breeding season. Hatching dates were recorded between the end of April and beginning of September, with an overall peak in July. Records of clutches on Lake Neuchâtel, where Red-crested Pochards nest mainly on artificial islands, indicate a high degree of interspecific nest parasitism, in particular with Mallard Anas platyrhynchos, the most abundant breeding duck species in Switzerland. Mixed families were commonly recorded as well. In most cases these were led by females of other species, mostly Mallard (80% of 219 families from across Switzerland), followed by Tufted Duck Aythya fuligula (16%), Common Pochard A. ferina (3%) and Common Eider Somateria mollissima (1%). Only in seven cases were ducklings from other species led by a Redcrested Pochard female. In six of these cases the family contained ducklings of Tufted Duck, in one of Mallard.
We used egg addition experiments and naturally parasitised nests of Common Pochard Aythya ferina and Tufted Duck A. fuligula to look for three host responses to brood parasitism; nest abandonment, egg discrimination, and between-year nest site movement. Parasitised females did not abandon nests more often (P = 0.26), discriminate against parasite eggs (P's ≥ 0.38), or move their nests a greater distance (P's ≥ 0.39) than nonparasitised females for either species. Host female Common Pochards and Tufted Ducks do not discriminate against parasitic eggs once they are added to the nest.
Interspecific brood amalgamation in waterfowl has been hypothesized to be an extension of intraspecific brood amalgamation behavior that increases the likelihood of successful amalgamation by increasing the range of potential recipients. I tested this hypothesis using recent phylogenetic information. The analysis revealed that the likelihood that a lineage carries the interspecific brood amalgamation state increases significantly when the lineage also carries the intraspecific amalgamation state, thus supporting the hypothesis. The likelihood of a transition to interspecific brood amalgamation was similar across categories of several ecological and life-history factors, including nesting dispersion, nesting substrate, type of brood care, and level of reproductive effort. Nevertheless, several lineages carrying the intraspecific brood amalgamation state failed to show the interspecific counterpart, suggesting that the expression of interspecific brood amalgamation tendencies can be constrained by other factors.
North American Ruddy Ducks (Oxyura jamaicensis) and Redheads (Aythya americana) lay eggs parasitically in other waterfowl nests. Interspecific egg parasitism at Farmington Bay Waterfowl Management Area (WMA), Utah during 1972-1974 affected 290 (36%) of 809 duck nests. Redheads deposited 812 eggs into 264 nests of other species, whereas Ruddy Ducks deposited 146 eggs into 62 nests. Of 620 Redhead eggs deposited interspecifically and for which success rates were known, 21% hatched, compared with 24% of 146 Ruddy Duck eggs. Forty-three percent of the Redheads and 7% of the Ruddy Ducks produced on the study site hatched from eggs deposited interspecifically. An unknown number of Redhead and Ruddy ducklings hatched from eggs deposited intraspecifically. Rates of egg parasitism in Redheads and Ruddy Ducks did not increase in response to severe fluctuations in water levels affecting habitat used by nesting waterfowl, nor was a lack of suitable nesting cover associated with Redhead or Ruddy Duck parasitism. These results counter the contention that parasitic tendencies in the Redhead, and perhaps the Ruddy Duck, are environmentally induced.
Dump nesting (2 or more hens laying eggs in 1 nest box) was a common phenomenon in a population of wood ducks (Aix sponsa) in southeastern Missouri. Nesting attempts increased from 47 in 1966 to 181 in 1974. Percentage of young from dump nests increased from 22 in 1966 to 86 in 1974. The additional production from dump nesting represented 23% of the young produced. Survival rates for young from normal and dump nests were similar. Dump nesting was not age related. Dump nesting females visited nest boxes before laying and some dumped eggs before nesting normally. Females tended to tolerate intrusion by other females during laying but repulsed intruders during incubation. Parasitic and host females derived maximum benefit from the limited nest sites available because of their behavioral characteristics.
Of 809 duck nests found at Farmington Bay Waterfowl Management Area, Farmington, Utah, 290 were parasitized interspecifically-264 by redheads (Aythya americana) and 62 by rudy ducks (Oxyura jamaicensis). Pintail (Anas acuta) and cinnamon teal (A. cyanoptera) nests most frequently incurred redhead parasitism, whereas cinnamon teal and redhead nests were most often parasitized by ruddy ducks. Mallard (A. platyrhynchos), pintail, and cinnamon teal nests parasitized interspecifically by ruddy ducks and redheads had significantly reduced (P < 0.05) egg successes. Egg success of cinnamon teal was significantly reduced (P < 0.05) through host egg displacement, primarily as a result of redhead parasitism. Egg displacement resulting from interspecific parasitism had a negligible effect on mallard, pintail, and redhead egg success. Redhead and ruddy duck interspecific parasitism did not decrease significantly (P > 0.05) host nesting success by increasing the occurrence of nest abandonment and nest predation.
V ERY little work has been done on ducks nesting among larids. During a study on the ecological interactions between two sympatric gull species, Larus californicus and L. delawarensis, on two islands, A and B, in Miquelon Lake, located at 53" 15' N and 112" 55' W in Alberta, data were collected of ducks nesting among these gulls in 1964 and 1965. The two islands carried dense populations of both California and Ring-billed gulls. The islands A and B were composed of boulders, sand and clay and consisted of six and five acres, respectively. Their highest points were six feet above the lake level. A few small trees and shrubs grew on them such as Popzdus tremuloides, Salk sp., Cornus stolonifera, Ribes o.xyacanthoides and Rosa woodsii. The most common herbs were Sonchus arvensis, Cirsium arvense, Taraxacum officinale and Juncus balticus.