Digestive Adaptations of Phainopepla nitens Associated with the Eating of Mistletoe Berries

Effectiveness of seed dispersal by different species that feed on the fruits of Myrtillocactus geometrizans was evaluated, considering both quantity and quality of dispersal, in a patch of tropical deciduous forest in Zapotitlán de las Salinas. Effectiveness was estimated to be strongly influenced by the post-foraging movements of the frugivores, leading us to suggest that the quality component of seed dispersal occupies a central role in the assessment of disperser effectiveness and to expect that dispersers that stay in the tropical deciduous forest patch after foraging would have highest effectiveness. Birds were the principal dispersers of M. geometrizans. This was particularly true of Phainopepla nitens, since this species showed a high fidelity within the tropical deciduous forest. These observations emphasize that it is important to determine the post-foraging habits of seed dispersers that may move across vegetation patches over the landscape in order to obtain a complete assessment of their role in Neotropical environments.

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Social and Genetic Monogamy in Territorial and Loosely Colonial Populations of Phainopepla (Phainopepla Nitens)

The Auk ◽

10.1093/auk/119.3.770 ◽

2002 ◽

Vol 119 (3) ◽

pp. 770-777 ◽

Cited By ~ 1

Author(s):

Miyoko Chu ◽

Walter D. Koenig ◽

Alvaro Godinez ◽

Carl E. McIntosh ◽

Robert C. Fleischer

Keyword(s):

Dna Fingerprinting ◽

Social Systems ◽

Copulatory Behavior ◽

Food Resources ◽

Genetic Monogamy ◽

Multilocus Dna Fingerprinting ◽

Phainopepla Nitens ◽

Breeding Attempt ◽

Breeding Seasons ◽

Two Populations

Abstract We observed courtship and copulatory behavior in two populations of Phainopeplas (Phainopepla nitens) with contrasting social systems and used multilocus DNA fingerprinting to assess rates of extrapair fertilization (EPF). Phainopeplas from both territorial and loosely colonial populations copulated infrequently (≤2 times per day). No extrapair copulations (EPCs) were observed in either population. We found no evidence of EPFs in 48 nestlings from 25 nests. Thus, Phainopeplas appear to be both socially and genetically monogamous. However, Phainopeplas are not monogamous over their lifetimes—they do not retain mates from year to year and appear to switch mates between breeding localities within the same year. Compressed breeding seasons, geographically shifting food resources, and widespread breeding failures may favor monogamy during any given breeding attempt while allowing opportunities to switch mates between breeding localities and years.

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Thermal Consequences of Roost-site Selection: The Relative Importance of Three Modes of Heat Conservation

The Auk ◽

10.1093/auk/103.1.1 ◽

1986 ◽

Vol 103 (1) ◽

pp. 1-7 ◽

Cited By ~ 35

Author(s):

Glenn E. Walsberg

Keyword(s):

Forced Convection ◽

Air Temperature ◽

Site Selection ◽

Radiation Balance ◽

Relative Importance ◽

Phainopepla Nitens ◽

Heat Conservation ◽

Using Data ◽

Selection Of ◽

Thermal Relations

Abstract Thermal factors potentially important in the selection of nocturnal roosts by birds include shelter from wind, local increases in air temperature, and improvement in radiation balance. I analyze the relative importance of these three factors using data describing the thermal relations of Phainopepla nitens and the meteorological properties of winter roost sites selected by this species. Shelter from forced convection provides approximately 5 times more thermal benefit than improvement of radiation balance. Possible metabolic heating by the bird of air within the roost site is unimportant.

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Patterns of mistletoe infection in four Acacia species in a semi-arid southern African savanna

Journal of Tropical Ecology ◽

10.1017/s0266467412000387 ◽

2012 ◽

Vol 28 (5) ◽

pp. 523-526 ◽

Cited By ~ 10

Author(s):

Hilton G. T. Ndagurwa ◽

Peter J. Mundy ◽

John S. Dube ◽

Donald Mlambo

Keyword(s):

Host Plant ◽

Infection Intensity ◽

Tree Height ◽

Number Of Factors ◽

Large Trees ◽

Phainopepla Nitens ◽

Species Characteristics ◽

Good Proxy ◽

Del Rio ◽

Branch Size

In a range of systems, studies on mistletoe distribution on the host plant have documented a number of factors that affect their occurrence and spread (Aukema & Martinez del Rio 2002a, Bowie & Ward 2004, Overton 1996, Reid et al. 1995). These patterns can be determined by host specificity, environmental conditions, host plant characteristics (Martinez del Rio et al. 1995) and the movement patterns of dispersal agents (Aukema & Martinez del Rio 2002a, 2002b). In mistletoe plants, host choice can be considerably influenced by the advantages of interacting with relatively abundant hosts (Norton & Carpenter 1998, Norton & De Lange 1999). Besides the relative abundance of host species, characteristics such as branch size, age and height can have a strong effect on mistletoe attachment resulting in size-related mistletoe infection patterns (Overton 1994). Generally positive relationships between mistletoe infection and host size have been demonstrated worldwide (Donohue 1995, Martinez del Rio et al. 1996, Norton et al. 1997, Reid & Stafford Smith 2000) and they have been interpreted in terms of the preferences by dispersing birds to perch and feed in taller trees (Aukema & Martinez del Rio 2002a) and trees accumulating infections as they age (Overton 1994). Aukema & Martinez del Rio (2002a) reported more frequent perching in taller-than-average trees by the phainopepla (Phainopepla nitens), which is the principal disperser of the desert mistletoe Phoradendron californicum. Thus, visits by mistletoe-seed-dispersing birds, and therefore mistletoe seeds received, tend to increase with tree height (Aukema & Martinez del Rio 2002a). Using a simple metapopulation model, Overton (1994) predicted the frequency of parasitized trees to increase with host age. Therefore, assuming that size is a good proxy for age, large trees are likely to be more infected than smaller trees. Reid & Stafford Smith (2000), using experimentally disinfected trees, found that larger trees were disproportionately re-infected with mistletoes. This size–intensity relationship may be used to describe mistletoe infection patterns. However, several previous studies have shown size–intensity relationships to be weak (Aukema & Martinez del Rio 2002a, Donohue 1995, Overton 1994, Reid & Stafford Smith 2000). This indicates that other factors may be important in determining mistletoe infection intensity, including that already parasitized hosts of a specific height are more likely to receive seeds than non-parasitized hosts of the same height or dispersers are likely to be attracted to trees for reasons other than size (Aukema & Martinez del Rio 2002a).

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