Long-term seed survival and dispersal dynamics in a rodent-dispersed tree: testing the predator satiation hypothesis and the predator dispersal hypothesis

Zhishu Xiao, Zhibin Zhang, Charles Krebs

Research output: Contribution to journalArticle

46 Citations (Scopus)

Abstract

1. Mast seeding in animal-dispersed plants has previously been accounted for by two main hypotheses: the predator satiation hypothesis (that it increases seed survival and establishment before dispersal) and the predator dispersal hypothesis (that it increases seed dispersal or dispersal distance). However, neither hypothesis has been rigorously tested with simultaneous data on seed production, seed predation and seed dispersal by vertebrate seed predators. 2. We studied oil tea Camellia oleifera (Theaceae) seed production for eight years (2002–2009) in a subtropical forest in south-west China, and investigated how annual seed and rodent abundance determined per capita seed availability for rodent seed predators and seed dispersers and how seed and rodent abundance were related to seed dispersal and seed survival via scatter-hoarding. We predicted the patterns of seed dispersal and survival to test the two hypotheses about mast seeding. Edward’s long-tailed rat Leopoldamys edwardsi acted as the principal seed disperser of oil tea seeds because of scatter-hoarding, while other sympatric rodent species acted only as seed predators. 3. We first provided a reasonable method to estimate per capita seed availability based on annual seed abundance and annual metabolic rodent abundance (corrected for metabolic-scaling body mass of each rodent species). We found that annual seed abundance, annual metabolic rodent abundance and per capita seed availability all had some significant effects on different estimators of seed fates (including dispersal distances) across each stage from seedfall to seedling establishment. Both annual seed abundance and per capita seed availability were positively correlated with pre- dispersal seed survival, but negatively correlated with scatter-hoarding (and recaching), seed survival after dispersal and dispersal distances. However, annual metabolic rodent abundance had a positive effect on scatter-hoarding, but had a negative effect on the time to cache recovery. 4. Synthesis. Since greater seed production was associated with improvement in pre-dispersal survival of oil tea seeds but a reduction in dispersal (including secondary dispersal and dispersal distance), our long-term study indicates that, compared with the predator dispersal hypothesis, the predator satiation hypothesis provides a better mechanism predicting seed dispersal and seed survival in animal-dispersed plants by integrating seed abundance and animal abundance.
Original languageEnglish
Pages (from-to)1256-1264
Number of pages9
JournalJournal of Ecology
Volume101
DOIs
Publication statusPublished - 2013
Externally publishedYes

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satiety
rodent
rodents
predator
seed
predators
seeds
testing
seed dispersal
caching
seed crop production
tea
seed production
seeding
animal
oil
sowing
Camellia oleifera
Theaceae
oils

Cite this

@article{a01e735cf5c14887a959dd61ae4b88a7,
title = "Long-term seed survival and dispersal dynamics in a rodent-dispersed tree: testing the predator satiation hypothesis and the predator dispersal hypothesis",
abstract = "1. Mast seeding in animal-dispersed plants has previously been accounted for by two main hypotheses: the predator satiation hypothesis (that it increases seed survival and establishment before dispersal) and the predator dispersal hypothesis (that it increases seed dispersal or dispersal distance). However, neither hypothesis has been rigorously tested with simultaneous data on seed production, seed predation and seed dispersal by vertebrate seed predators. 2. We studied oil tea Camellia oleifera (Theaceae) seed production for eight years (2002–2009) in a subtropical forest in south-west China, and investigated how annual seed and rodent abundance determined per capita seed availability for rodent seed predators and seed dispersers and how seed and rodent abundance were related to seed dispersal and seed survival via scatter-hoarding. We predicted the patterns of seed dispersal and survival to test the two hypotheses about mast seeding. Edward’s long-tailed rat Leopoldamys edwardsi acted as the principal seed disperser of oil tea seeds because of scatter-hoarding, while other sympatric rodent species acted only as seed predators. 3. We first provided a reasonable method to estimate per capita seed availability based on annual seed abundance and annual metabolic rodent abundance (corrected for metabolic-scaling body mass of each rodent species). We found that annual seed abundance, annual metabolic rodent abundance and per capita seed availability all had some significant effects on different estimators of seed fates (including dispersal distances) across each stage from seedfall to seedling establishment. Both annual seed abundance and per capita seed availability were positively correlated with pre- dispersal seed survival, but negatively correlated with scatter-hoarding (and recaching), seed survival after dispersal and dispersal distances. However, annual metabolic rodent abundance had a positive effect on scatter-hoarding, but had a negative effect on the time to cache recovery. 4. Synthesis. Since greater seed production was associated with improvement in pre-dispersal survival of oil tea seeds but a reduction in dispersal (including secondary dispersal and dispersal distance), our long-term study indicates that, compared with the predator dispersal hypothesis, the predator satiation hypothesis provides a better mechanism predicting seed dispersal and seed survival in animal-dispersed plants by integrating seed abundance and animal abundance.",
keywords = "abundance, dispersal/survival trade-off, Edward’s long-tailed rat Leopoldamys edwardsi, mast seeding, predator satiation, scatter-hoarding, seed dispersal.",
author = "Zhishu Xiao and Zhibin Zhang and Charles Krebs",
year = "2013",
doi = "10.1111/1365-2745.12113",
language = "English",
volume = "101",
pages = "1256--1264",
journal = "Journal of Ecology",
issn = "0022-0477",
publisher = "Wiley-Blackwell",

}

Long-term seed survival and dispersal dynamics in a rodent-dispersed tree: testing the predator satiation hypothesis and the predator dispersal hypothesis. / Xiao, Zhishu; Zhang, Zhibin; Krebs, Charles.

In: Journal of Ecology, Vol. 101, 2013, p. 1256-1264.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Long-term seed survival and dispersal dynamics in a rodent-dispersed tree: testing the predator satiation hypothesis and the predator dispersal hypothesis

AU - Xiao, Zhishu

AU - Zhang, Zhibin

AU - Krebs, Charles

PY - 2013

Y1 - 2013

N2 - 1. Mast seeding in animal-dispersed plants has previously been accounted for by two main hypotheses: the predator satiation hypothesis (that it increases seed survival and establishment before dispersal) and the predator dispersal hypothesis (that it increases seed dispersal or dispersal distance). However, neither hypothesis has been rigorously tested with simultaneous data on seed production, seed predation and seed dispersal by vertebrate seed predators. 2. We studied oil tea Camellia oleifera (Theaceae) seed production for eight years (2002–2009) in a subtropical forest in south-west China, and investigated how annual seed and rodent abundance determined per capita seed availability for rodent seed predators and seed dispersers and how seed and rodent abundance were related to seed dispersal and seed survival via scatter-hoarding. We predicted the patterns of seed dispersal and survival to test the two hypotheses about mast seeding. Edward’s long-tailed rat Leopoldamys edwardsi acted as the principal seed disperser of oil tea seeds because of scatter-hoarding, while other sympatric rodent species acted only as seed predators. 3. We first provided a reasonable method to estimate per capita seed availability based on annual seed abundance and annual metabolic rodent abundance (corrected for metabolic-scaling body mass of each rodent species). We found that annual seed abundance, annual metabolic rodent abundance and per capita seed availability all had some significant effects on different estimators of seed fates (including dispersal distances) across each stage from seedfall to seedling establishment. Both annual seed abundance and per capita seed availability were positively correlated with pre- dispersal seed survival, but negatively correlated with scatter-hoarding (and recaching), seed survival after dispersal and dispersal distances. However, annual metabolic rodent abundance had a positive effect on scatter-hoarding, but had a negative effect on the time to cache recovery. 4. Synthesis. Since greater seed production was associated with improvement in pre-dispersal survival of oil tea seeds but a reduction in dispersal (including secondary dispersal and dispersal distance), our long-term study indicates that, compared with the predator dispersal hypothesis, the predator satiation hypothesis provides a better mechanism predicting seed dispersal and seed survival in animal-dispersed plants by integrating seed abundance and animal abundance.

AB - 1. Mast seeding in animal-dispersed plants has previously been accounted for by two main hypotheses: the predator satiation hypothesis (that it increases seed survival and establishment before dispersal) and the predator dispersal hypothesis (that it increases seed dispersal or dispersal distance). However, neither hypothesis has been rigorously tested with simultaneous data on seed production, seed predation and seed dispersal by vertebrate seed predators. 2. We studied oil tea Camellia oleifera (Theaceae) seed production for eight years (2002–2009) in a subtropical forest in south-west China, and investigated how annual seed and rodent abundance determined per capita seed availability for rodent seed predators and seed dispersers and how seed and rodent abundance were related to seed dispersal and seed survival via scatter-hoarding. We predicted the patterns of seed dispersal and survival to test the two hypotheses about mast seeding. Edward’s long-tailed rat Leopoldamys edwardsi acted as the principal seed disperser of oil tea seeds because of scatter-hoarding, while other sympatric rodent species acted only as seed predators. 3. We first provided a reasonable method to estimate per capita seed availability based on annual seed abundance and annual metabolic rodent abundance (corrected for metabolic-scaling body mass of each rodent species). We found that annual seed abundance, annual metabolic rodent abundance and per capita seed availability all had some significant effects on different estimators of seed fates (including dispersal distances) across each stage from seedfall to seedling establishment. Both annual seed abundance and per capita seed availability were positively correlated with pre- dispersal seed survival, but negatively correlated with scatter-hoarding (and recaching), seed survival after dispersal and dispersal distances. However, annual metabolic rodent abundance had a positive effect on scatter-hoarding, but had a negative effect on the time to cache recovery. 4. Synthesis. Since greater seed production was associated with improvement in pre-dispersal survival of oil tea seeds but a reduction in dispersal (including secondary dispersal and dispersal distance), our long-term study indicates that, compared with the predator dispersal hypothesis, the predator satiation hypothesis provides a better mechanism predicting seed dispersal and seed survival in animal-dispersed plants by integrating seed abundance and animal abundance.

KW - abundance

KW - dispersal/survival trade-off

KW - Edward’s long-tailed rat Leopoldamys edwardsi

KW - mast seeding

KW - predator satiation

KW - scatter-hoarding

KW - seed dispersal.

U2 - 10.1111/1365-2745.12113

DO - 10.1111/1365-2745.12113

M3 - Article

VL - 101

SP - 1256

EP - 1264

JO - Journal of Ecology

JF - Journal of Ecology

SN - 0022-0477

ER -