Fruit selection by birds in relation to fruit abundance and appearance in the naturalised shrub <i>Berberis darwinii</i>

Allen, Robert B.; Lee, W.G.

doi:10.1080/0028825x.1992.10412892

Cited by 16 publications

(13 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…obs. ), and fruits earlier in the season than many other plant species in New Zealand (Allen and Lee 1992). All of these factors support previous suggestions that B. darwinii is a prolific fruit producer with highly effective seed dispersal mechanisms (Allen and Wilson 1992).…”

Section: Discussionsupporting

confidence: 71%

Linking seed dispersal, germination and seedling recruitment in the invasive species Berberis darwinii (Darwin’s barberry)

McAlpine

Jesson

2007

Plant Ecol

View full text Add to dashboard Cite

Seedling recruitment is a multi-phased process involving seed production, dispersal, germination, seedling establishment and subsequent survival. Understanding the factors that determine success at each stage of this process is of particular interest to scientists and managers seeking to understand how invasive species spread and persist, and identify critical stages for management. To understand the factors and processes influencing recruitment of the invasive species Berberis darwinii Hook. (Darwin's barberry), temporal and spatial patterns of seed dispersal, germination and seedling establishment were examined. Seed dispersal from a large source population was measured over two fruiting seasons, and subsequent patterns of seedling emergence and survival within each cohort were measured. Seed longevity was tested under both natural and artificial conditions. Seeds were widely dispersed by birds, up to 450 m from the source population. Dispersal was essential to seedling establishment, as few seedlings survived beneath the parent canopy. Seeds were relatively short-lived in the soil under both field and glasshouse conditions, with few surviving for more than 1 year. Patterns of newly emerged seedlings largely reflected patterns of seed rain, but seedling survival was significantly affected by distance from source population, seedling density and light environment. These results suggest that recruitment of B. darwinii is dependent on dispersal of seeds to favourable microsites. Management priorities should include the removal of fruiting plants, and seedling control in highlight areas.

show abstract

Section: Discussionsupporting

confidence: 71%

Linking seed dispersal, germination and seedling recruitment in the invasive species Berberis darwinii (Darwin’s barberry)

McAlpine

Jesson

2007

Plant Ecol

View full text Add to dashboard Cite

show abstract

“…How- Day Total no. of fruits consumated ever, although larger fruit crops do often attract more frugivorous birds (DAVIDAR & MORTON 1986, DENSLOW 1987, MCPHERSON 1987, MURRAY 1987, FOSTER 1990, WIL-LIAMS & KARL 1996 and induce a greater overall feeding rate, they are not generally exploited disproportionately more than smaller crops in nature (DAVIDAR & MORTON 1986, MURRAY 1987, ALLEN & LEE 1992. Unlike the present study, however, the latter field-based investigations did not control variables other than fruit abundance.…”

Section: Relative Abundance and Fruit Colour Choicecontrasting

confidence: 67%

The effect of fruit abundance, conspicuousness and sugar concentration on fruit colour choice by captive silvereyes

Giles

Lill

1999

Ethology Ecology & Evolution

View full text Add to dashboard Cite

Wild-caught, captive silvereyes (Zosterops lateralis, Zosteropidae) were given choice tests to determine how some traits of fleshy fruits interact to influence fruit selection by this facultative frugivore. When given a choice between red and white fruits of the polymorphic Fragrant saltbush (Rhagodia parabolica, Chenopodiaceae), the silvereyes' preference for the red fruits was enhanced when they were twice as abundant, but reversed when they were only half as abundant, as the white fruits. Given a choice between red and white artificial fruits, silvereyes showed a 2.3-fold preference for the latter when both were equally conspicuous; this preference was significantly enhanced when the white fruits were relatively more conspicuous (greater contrast with the background colour), but eliminated when they were relatively more cryptic (less contrast with the background colour). A third experiment showed that the sugar concentration of artificial fruits influenced the birds' fruit colour preference, enhancing it by a factor of 8 when the preferred colour was relatively sugar-rich, but eliminating it when the preferred colour was relatively sugar-poor. The results are discussed in the context of current hypotheses about fruit selection processes in birds.

show abstract

“…Bellbirds rarely include exotic fruits in their diet (Allen & Lee 1992;O'Donnell & Dilks 1994;Williams & Karl 1996), and ate no exotics in our study, ignoring abundant B. glaucocarpa fruits. Blackbirds are considered one of the top dispersers of exotic fruiting plants in New Zealand (Williams & Karl 1996).…”

Section: Is Weed Spread By Exotic Birds a Problem?mentioning

confidence: 96%

Introduced blackbirds and song thrushes: useful substitutes for lost mid-sized native frugivores, or weed vectors?

MacFarlane¹,

Kelly²,

Briskie³

2016

NZ J Ecol

View full text Add to dashboard Cite

Abstract:The New Zealand avifauna has declined from human impacts, which might leave some larger-seeded native plants vulnerable to dispersal failure. We studied fruit dispersal in a lowland secondary forest near Kaikoura, where the only remaining native frugivores are relatively small (silvereye Zosterops lateralis, and bellbird Anthornis melanura). We tested whether two larger exotic frugivores (blackbird Turdus merula and song thrush T. philomelos) dispersed native plants with seeds too large for the two smaller native frugivores. Diet breadth was measured by identifying seeds in the faeces of 221 mist-netted birds, and by observations of birds foraging. We then compared the plant species dispersed to the range of locally available fruits. All four bird species had varied diets (6-9 plant species per bird species) that differed significantly, although Coprosma robusta was always the most-eaten fruit. As predicted, the maximum fruit size eaten was larger for exotic birds (11.3 mm diameter) than natives (7.4-7.7 mm diameter), but all birds ate mainly smaller fruits. However, 7/21 fruiting plant species were not seen to be dispersed by any species, and the chance of being undispersed was independent of fruit size. Blackbirds and song thrushes jointly dispersed all four woody weeds with fruits >7.5 mm diameter, but neither of the two similar-sized native plants. Although the two species of exotic birds dispersed some native plants, our study suggests that their net effect is negative through facilitating the spread of invasive weeds. Studies evaluating the contribution of exotic frugivores to novel plant communities need to distinguish potential effects (what the frugivores might be capable of doing) from actual effects (what the frugivores are observed doing).

show abstract

Fruit selection by birds in relation to fruit abundance and appearance in the naturalised shrub Berberis darwinii

Cited by 16 publications

References 12 publications

Linking seed dispersal, germination and seedling recruitment in the invasive species Berberis darwinii (Darwin’s barberry)

Linking seed dispersal, germination and seedling recruitment in the invasive species Berberis darwinii (Darwin’s barberry)

The effect of fruit abundance, conspicuousness and sugar concentration on fruit colour choice by captive silvereyes

Introduced blackbirds and song thrushes: useful substitutes for lost mid-sized native frugivores, or weed vectors?

Contact Info

Product

Resources

About