Foraging behaviour of brent geese, Branta b. bernicla, on grasslands: effects of sward length and nitrogen content
Feeding behaviour and preferences of brent geese, Branta b. bernicla were observed on pastures of different sward lengths and nitrogen contents. On swards of 2.0-6.0 cm captive geese took larger bites and had a higher intake rate when feeding on 6-cm swards than when feeding on shorter ones. In the...
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2001
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ftuniveastangl:oai:ueaeprints.uea.ac.uk:31211 2023-05-15T15:46:31+02:00 Foraging behaviour of brent geese, Branta b. bernicla, on grasslands: effects of sward length and nitrogen content Hassall, Mark Riddington, Roger Helden, Alvin 2001 https://ueaeprints.uea.ac.uk/id/eprint/31211/ https://doi.org/10.1007/s004420000563 unknown Hassall, Mark, Riddington, Roger and Helden, Alvin (2001) Foraging behaviour of brent geese, Branta b. bernicla, on grasslands: effects of sward length and nitrogen content. Oecologia, 127 (1). pp. 97-104. ISSN 0029-8549 doi:10.1007/s004420000563 Article PeerReviewed 2001 ftuniveastangl https://doi.org/10.1007/s004420000563 2023-01-30T21:29:42Z Feeding behaviour and preferences of brent geese, Branta b. bernicla were observed on pastures of different sward lengths and nitrogen contents. On swards of 2.0-6.0 cm captive geese took larger bites and had a higher intake rate when feeding on 6-cm swards than when feeding on shorter ones. In the field wild geese chose 6-cm swards in preference to both shorter and longer ones. For unfertilized pastures there was a strong negative relationship between nitrogen content and sward height: 11-cm swards contained 2.8% nitrogen, 3.5-cm swards 4.2% nitrogen. Application of 75 kg N ha-1 organically based fertilizer at the end of October eliminated this relationship between nitrogen content and sward height, swards of all heights then having a mean content of 4.1% N. On fertilized plots the geese preferred swards longer than 6 cm with no indication of a decrease in preference up to the maximum height investigated, 16 cm. Breaking strain of grass laminae was measured to give an indication of the proportion of strengthening tissues in the leaves and hence their digestibility. Apical laminae from longer swards had a higher breaking strain than those from shorter swards. Unfertilized swards had a higher breaking strain than fertilized swards but the difference in breaking strain between long and short swards was the same on fertilized and control treatments. These results are discussed in relation to the forage maturation hypothesis and are interpreted as indicating that the primary constraint on maximizing energy intake rates is not the reduced energy digestibility of older foliage but the reduced nitrogen content in the higher-biomass swards. We conclude that it is the balance between maximizing energy intake and nitrogen absorption rates which results in the observed preference for intermediate-height swards. Article in Journal/Newspaper brent geese University of East Anglia: UEA Digital Repository Oecologia 127 1 97 104 |
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Open Polar |
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University of East Anglia: UEA Digital Repository |
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ftuniveastangl |
language |
unknown |
description |
Feeding behaviour and preferences of brent geese, Branta b. bernicla were observed on pastures of different sward lengths and nitrogen contents. On swards of 2.0-6.0 cm captive geese took larger bites and had a higher intake rate when feeding on 6-cm swards than when feeding on shorter ones. In the field wild geese chose 6-cm swards in preference to both shorter and longer ones. For unfertilized pastures there was a strong negative relationship between nitrogen content and sward height: 11-cm swards contained 2.8% nitrogen, 3.5-cm swards 4.2% nitrogen. Application of 75 kg N ha-1 organically based fertilizer at the end of October eliminated this relationship between nitrogen content and sward height, swards of all heights then having a mean content of 4.1% N. On fertilized plots the geese preferred swards longer than 6 cm with no indication of a decrease in preference up to the maximum height investigated, 16 cm. Breaking strain of grass laminae was measured to give an indication of the proportion of strengthening tissues in the leaves and hence their digestibility. Apical laminae from longer swards had a higher breaking strain than those from shorter swards. Unfertilized swards had a higher breaking strain than fertilized swards but the difference in breaking strain between long and short swards was the same on fertilized and control treatments. These results are discussed in relation to the forage maturation hypothesis and are interpreted as indicating that the primary constraint on maximizing energy intake rates is not the reduced energy digestibility of older foliage but the reduced nitrogen content in the higher-biomass swards. We conclude that it is the balance between maximizing energy intake and nitrogen absorption rates which results in the observed preference for intermediate-height swards. |
format |
Article in Journal/Newspaper |
author |
Hassall, Mark Riddington, Roger Helden, Alvin |
spellingShingle |
Hassall, Mark Riddington, Roger Helden, Alvin Foraging behaviour of brent geese, Branta b. bernicla, on grasslands: effects of sward length and nitrogen content |
author_facet |
Hassall, Mark Riddington, Roger Helden, Alvin |
author_sort |
Hassall, Mark |
title |
Foraging behaviour of brent geese, Branta b. bernicla, on grasslands: effects of sward length and nitrogen content |
title_short |
Foraging behaviour of brent geese, Branta b. bernicla, on grasslands: effects of sward length and nitrogen content |
title_full |
Foraging behaviour of brent geese, Branta b. bernicla, on grasslands: effects of sward length and nitrogen content |
title_fullStr |
Foraging behaviour of brent geese, Branta b. bernicla, on grasslands: effects of sward length and nitrogen content |
title_full_unstemmed |
Foraging behaviour of brent geese, Branta b. bernicla, on grasslands: effects of sward length and nitrogen content |
title_sort |
foraging behaviour of brent geese, branta b. bernicla, on grasslands: effects of sward length and nitrogen content |
publishDate |
2001 |
url |
https://ueaeprints.uea.ac.uk/id/eprint/31211/ https://doi.org/10.1007/s004420000563 |
genre |
brent geese |
genre_facet |
brent geese |
op_relation |
Hassall, Mark, Riddington, Roger and Helden, Alvin (2001) Foraging behaviour of brent geese, Branta b. bernicla, on grasslands: effects of sward length and nitrogen content. Oecologia, 127 (1). pp. 97-104. ISSN 0029-8549 doi:10.1007/s004420000563 |
op_doi |
https://doi.org/10.1007/s004420000563 |
container_title |
Oecologia |
container_volume |
127 |
container_issue |
1 |
container_start_page |
97 |
op_container_end_page |
104 |
_version_ |
1766381200469917696 |