POSTER ABSTRACTS Birds in the entangled bank: advances in food webs theory and practice BOU Autumn Conference | Peterborough, UK | 19 November 2014 | Twitter #BOU2014 Endozoochory largely outweighs epizoochory in migrating
passerines
JOSÉ MIGUEL COSTA
University of Coimbra, Portugal
[email protected]
Fruit is a critical food source for many European passerines during the autumn
migration, which in turn contribute to disperse their seeds either internally, i.e. after
ingestion (endozoochory), or externally, when seeds adhere to the body surface
(epizoochory). Despite the recognized importance of birds as seed dispersers, the vast
majority of studies focused on endozoochory while the external transport of seeds is
frequently invoked as being potentially important, but remains largely unexplored. This
is particularly important during the post-breeding migration of passerines, the most
ubiquitous and diverse movement of potential seed carriers across Europe and into
Africa, which coincides with the fruiting peak of many plant species (August-October).
Our aim was to evaluate the role of migrating birds as potential long-distance seed
dispersers, and comparing the prevalence of epizoochory and endozoochory during
post-breeding migration. We sampled 926 wild birds in nine locations in Portugal, and
retrieved 1,833 seeds of 19 plant species dispersed internally and only three seeds
externally attached to three birds (Serinus serinus, Locustella naevia and Turdus merula),
showing an endozoochory prevalence 85 times higher than that of epizoochory .
Migrating and non-migrating passerines dispersed seeds equally. While two of the seeds
transported externally had specific adaptations to epizoochory, namely spines (Torilis
arvensis) and hooks (Galium aparine), the third, a large seed from a fleshy-fruited plant,
Frangula alnus, is usually dispersed via endozoochory. These seeds were found on bird
species with different diets, but similar behaviour (ground foragers) and in similar
habitats (open agro-ecosystems). Our results highlight the strong role of migrating
passerines as potentially long-distance seed dispersers and show that, at least in the
autumn, the prevalence of epizoochory is several orders of magnitude lower than that of
endozoochory.
© The Authors & BOU, 2014 1 POSTER ABSTRACTS Birds in the entangled bank: advances in food webs theory and practice BOU Autumn Conference | Peterborough, UK | 19 November 2014 | Twitter #BOU2014 Bird pollination in Europe: irrelevant or underappreciated?
LUÍS P. DA SILVA
H. HELENO
1
1,2
1
3
4
*, JAIME A. RAMOS , JENS M. OLESEN , ANNA TRAVESET & RUBEN
2
Marine and Environmental Research Centre (IMAR/CMA), Department of Life Sciences,
University of Coimbra, Coimbra, Portugal.
2
Centre for Functional Ecology, Department of Life Sciences, University of Coimbra,
Coimbra, Portugal.
3
Department of Bioscience, Aarhus University, Aarhus, Denmark,
4
Mediterranean Institute of Advanced Studies (CSIC-UIB), Terrestrial Ecology Group,
Mallorca, Balearic Islands
* [email protected]
Most flowering plants depend on animal pollination. Several animal groups, including
many birds, have specialized in exploiting floral nectar, while simultaneously pollinating
the flowers they visit. These specialized pollinators are present in all continents except
Europe and Antarctica, and thus, insects are often considered the only ecologically
relevant pollinators in Europe. Nevertheless, generalist birds are also known to visit
flowers, and several reports of flower visitation by birds in this continent prompted us to
review available information in order to estimate its prevalence. We retrieved reports of
flower-bird interactions from 62 publications. Forty-six bird species visited the flowers of
95 plant species, 26 of these being exotic to Europe, yielding a total of 243 specific
interactions. The ecological importance of bird-flower visitation in Europe is still
unknown, particularly in terms of plant reproductive output, but effective pollination has
been confirmed for several native and exotic plant species. We suggest nectar and pollen
to be important food resources for several bird species, especially tits (Cyanistes), and
Sylvia and Phylloscopus warblers during winter and spring. The prevalence of bird flowervisitation, and thus potential bird pollination, is slightly more common in the
Mediterranean basin, which is a stopover to many migrant bird species, which might
actually increase their effectiveness as pollinators by promoting long-distance pollen
flow. We argue that research on bird pollination in Europe deserves further attention to
explore its ecological and evolutionary relevance.
© The Authors & BOU, 2014 2 POSTER ABSTRACTS Birds in the entangled bank: advances in food webs theory and practice BOU Autumn Conference | Peterborough, UK | 19 November 2014 | Twitter #BOU2014 Simulating the effects of climate-warming on farm ecosystem
services: new technologies for agri-sciences
1
1
2
3
STEPHANE A.P. DEROCLES *, DAVID H. LUNT , JONATHAN ATKINS , GUY HEMBURY &
DARREN M. EVANS
1
1
Department of Biological Sciences, University of Hull, Cottingham Road, Hull HU6 7RX,
UK
2
Hull University Business School (HUBS), University of Hull, Cottingham Road, Hull HU6
7RX, UK
3
Centre for Adaptive Science & Sustainability (CASS), University of Hull, Cottingham Road,
Hull HU6 7RX, UK
* [email protected]
Increasing greenhouse gas emissions are expected to raise global mean temperature by
2–7°C by the end of this century. Precipitation is projected to increase at high latitudes
and decrease in most subtropical regions. Because temperature and precipitation are
important drivers of ecosystem processes, climate change will likely affect ecosystem
functioning although the potential impacts are unclear. Moreover, predicting how
warming will affect ecosystem services, such as crop pollination and insect pest control,
is a key challenge.
We investigate the ecological and economic costs of simulated climate change on a
farmland ecosystem. With a focus on wheat yields, we use a fully-replicated experiment
to increase temperature by 2°C and precipitation by 10%. We measure the impact of this
simulated climate change on three trophic levels in an agroecosystem: 1) the plants, 2)
the herbivores (i.e. aphids as major crop pests), 3) the predators (e.g. aphid parasitoids).
Next, we us a molecular approach based on DNA barcoding specifically developed for
this project to identify trophic interactions. We then determine the impact of the
treatments on the ecological network of plants, aphids and associated parasitoids.
For the first time in an open field experiment, we demonstrate the impact of a simulated
climate warming on tri-partite ecological networks. First, we observe the effect of
experimental warming on plant quality, plant community structure and crop yield. For
the second trophic level, we show an earlier and more important colonisation of aphids
within warmed plots: aphid outbreaks increase and then lead to a loss of crop yields. We
capture substantially more beetles (Coleoptera: Carabidae) and aphid parasitoids in
warmed plots: an increase in the abundance of these predators may lead to top-down
effects. Finally, our molecular approach shows that a simulate climate change modify the
structure of tri-partite networks.
© The Authors & BOU, 2014 3 POSTER ABSTRACTS Birds in the entangled bank: advances in food webs theory and practice BOU Autumn Conference | Peterborough, UK | 19 November 2014 | Twitter #BOU2014 Our approach enable us to considerably improve our knowledge about the impact of
climate change on farmland ecosystem services and help producers to develop ways of
harnessing the ecosystem services provided by biodiversity more generally.
How does light pollution affect nocturnal pollination interactions?
An ecological network approach
1,2
2
3
CALLUM J. MACGREGOR , MICHAEL J. O. POCOCK , RICHARD FOX &
DARREN M. EVANS
1
1
School of Biological, Biomedical and Environmental Sciences, University of Hull,
Cottingham Road, Hull, HU6 7RX, UK.
2
Centre for Ecology & Hydrology, Maclean Building, Benson Lane, Crowmarsh Gifford,
Wallingford, Oxfordshire, OX10 8BB, UK.
3
Butterfly Conservation, Manor Yard, East Lulworth, Wareham, Dorset, UK.
* [email protected]
Moths are in decline both in the UK and abroad; one of the proposed drivers of this
decline is light pollution. Although moths are often overlooked as one of the most
important groups of pollinators, the moth-pollination strategy may carry selective
advantages and moths have been shown to be important pollinators in a range of
species and systems. Moths are affected by artificial light in a variety of ways; however,
no studies have yet investigated effects upon moths at the community level, or upon
interactions between moths and plants.
An ecological network approach is one valuable method to consider the effects of
artificial night lighting upon the provision of pollination by moths. We hypothesise some
of the ways in which plant-moth pollination networks may change as a result of artificial
night lighting. We conclude that pollination by moths is an ecosystem process that may
potentially be disrupted by increasing light pollution, although the nature of this
disruption remains to be tested.
© The Authors & BOU, 2014 4 POSTER ABSTRACTS Birds in the entangled bank: advances in food webs theory and practice BOU Autumn Conference | Peterborough, UK | 19 November 2014 | Twitter #BOU2014 The Impacts of Habitat Modification on Avian Food-Web Structure
and Resilience
1,2
2
2
3
LISA MALM *, NICK LITTLEWOOD , ALI KARLEY , JAMES PEARCE-HIGGINS &
DARREN EVANS
1
1
University of Hull, UK
2
James Hutton Institute, UK
3
British Trust for Ornithology, UK
* Email: [email protected]
Changes in landscape management and habitat modifications are common reasons for
declines of many bird species. To understand the cause of these declines in insectivorous
species, we need a better understanding of how their foraging resources are affected.
New non-invasive methods of analysing food web structure and composition are
necessary to understand their robustness to environmental change. A burgeoning
number of studies have shown that it is possible to identify the DNA of prey species
found in avian faeces, but few have used this approach to construct and analyse avian
food-webs.
In this project we will develop molecular techniques to identify the prey of a range of
upland insectivorous birds. In particular, we will assess how livestock grazing pressure
affects the food-web structure of a common upland passerine: the meadow pipit.
Molecular methods will be evaluated by comparing the results to those found by
identifying the species of the prey that are fed to meadow pipit chicks.
The study will be carried out in Glen Finglas, Scotland, where a long term experiment
examining the effects of different grazing intensities on upland plant and animal has
been running since 2003. Previous studies have investigated the relationship between
grazing intensity and abundance and foraging behaviour of breeding meadow pipits. It
has been shown that meadow pipits prefer to search for food on low intensity grazed
spots and that they mainly feed Lepidoptera larvae, adult Tipulidae and Arachnids to
their chicks. It has also been shown that the right vegetation structure for arthropod
availability is more important than a high arthropod abundance as a separate factor. In
this study, we will also investigate the effects of different levels of grazing intensity on the
composition of arthropod prey that will be identified to species. By comparing the
diversity and different quantities of the prey composition between different grazing
intensities we can better understand how ground foraging birds such as meadow pipits
are affected by the landscape management.
© The Authors & BOU, 2014 5 POSTER ABSTRACTS Birds in the entangled bank: advances in food webs theory and practice BOU Autumn Conference | Peterborough, UK | 19 November 2014 | Twitter #BOU2014 Morphological and spatio-temporal mismatches shape a neotropical
savanna plant-hummingbird network
PIETRO K. MARUYAMA
1,4,*
3
PAULO E. OLIVEIRA & BO DALSGAARD
1
1
2
, JEFERSON VIZENTIN-BUGONI , GENILDA M. OLIVEIRA ,
4
Programa de Pós-Graduacão em Ecologia, Universidade Estadual de Campinas
(UNICAMP), Cx. Postal 6109, CEP: 13083-862, Campinas, SP, Brazil
2
Instituto Federal do Triângulo Mineiro, Campus Uberlândia. Fazenda Sobradinho, CP
1020, Zona Rural, Cep 38400-970. Uberlândia, MG, Brazil
3
Instituto de Biologia, Universidade Federal de Uberlândia -UFU, Cx. Postal 593, CEP
38400-902, Uberlândia, MG, Brazil
4
Center for Macroecology, Evolution and Climate, Natural History Museum of Denmark,
University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen Ø, Denmark
* [email protected]
Complex networks of species interactions might be determined by species traits but also
by simple chance meetings governed by species abundances. Although the idea that
species traits structure mutualistic networks is appealing, most studies have found
abundance to be a major structuring mechanism underlying interaction frequencies.
With a well-resolved plant-hummingbird interaction network from the Neotropical
savanna in Brazil, we asked whether species morphology, phenology, nectar availability
and habitat occupancy and/or abundance best predicted the frequency of interactions.
For this, we constructed interaction probability matrices and compared them to the
observed plant-hummingbird matrix through a likelihood approach. Furthermore, a
recently proposed modularity algorithm for weighted bipartite networks was employed
to evaluate whether these factors also scale-up to the formation of modules in the
network. Interaction frequencies were best predicted by species morphology, phenology
and habitat occupancy, while species abundances and nectar availability performed
poorly. The plant-hummingbird network was modular, and modules were associated to
morphological specialization and habitat occupancy. Our findings highlight the
importance of traits as determinants of interaction frequencies and network structure,
corroborating the results of a previous study on a plant-hummingbird network from the
Brazilian Atlantic Forest. Thus, we propose that traits matter more in tropical planthummingbird networks than in less specialized systems. To test the generality of this
hypothesis, future research could employ geographic or taxonomic cross-system
comparisons contrasting networks with known differences in level of specialization.
© The Authors & BOU, 2014 6 POSTER ABSTRACTS Birds in the entangled bank: advances in food webs theory and practice BOU Autumn Conference | Peterborough, UK | 19 November 2014 | Twitter #BOU2014 The impacts of simulated climate warming on plant-pollinator
interactions and ecosystem services in UK agro-ecosystems
1
2
ELLEN D. MOSS *, JONATHAN ATKINS & DARREN M. EVANS
1
1
School of Biological, Biomedical & Environmental Sciences, University of Hull, UK
2
Hull University Business School, University of Hull, UK
* [email protected]
Agro-ecosystems are under increasing pressure to provide high yields of varied and high
quality food to support a growing population, whilst at the same time preventing further
loss of biodiversity and providing measures to increase it. Climate change is predicted to
further complicate this situation by affecting the delivery of ecosystem services.
Pollination is an extremely important service in terms of food and biofuel production, it
has been calculated to be worth £430 million to the UK economy. Pollination is also
essential for biodiversity conservation as 78% of all temperate plant species are animalpollinated.
Declines in pollinator species diversity and abundance have been well documented in
recent years and are attributed to a number of factors including habitat loss and disease.
Parallel declines have also been documented in insect-pollinated plants. Climate change
is expected to exacerbate these declines via several mechanisms, including: forcing
species range shifts, loss of specialists, and altering phenology, all of which could affect
pollination service provision and lead to loss of biodiversity.
This project uses a completely open field-experiment employing infra-red heaters to
simulate climate-warming, in an arable farmland setting. Using a bottom-up approach
we will determine how increasing temperature by 2 °C and precipitation by 10%, will
affect arable weed growth, development, resources, and health, and in turn, how wild
pollinator visitation varies. We will construct and analyse highly resolved plant-pollinator
interaction networks to provide the first experimental evidence of how pollinator
community structure, composition and robustness are affected by climate change. In
addition, seed collection and analysis will allow a direct measure of pollination quality
and yield across our experimental treatments.
This research is part of a larger project which is also investigating how climate change
will affect other organisms responsible for ecosystem service delivery, including pest
regulation of wheat by parasitoid wasps.
© The Authors & BOU, 2014 7 POSTER ABSTRACTS Birds in the entangled bank: advances in food webs theory and practice BOU Autumn Conference | Peterborough, UK | 19 November 2014 | Twitter #BOU2014 Mutualistic plant-frugivore networks and their impacts on seedling
establishment in tropical montane forest
MARCIA C. MUÑOZ
1,2,*
MATTHIAS SCHLEUNING
1
3
, H. MARTIN SCHAEFER , KATRIN BÖHNING-GAESE
1,2
&
1
Biodiversity and Climate Research Centre (BiK-F) & Senckenberg Gesellschaft für
Naturforschung, Senckenberganlage 25, 60325, Frankfurt am Main, Germany
2
Department of Biological Sciences, Goethe Universität, Max-von-Laue-Straße 9, 60438,
Frankfurt am Main, Germany
3
Department of Evolutionary Biology and Animal Ecology, Faculty of Biology, University
of Freiburg, Hauptstrasse 1, 79104, Freiburg, Germany
*Email: [email protected]
Seedling establishment is a key process with important implications for plant
demography and forest regeneration. Most tropical woody plant species depend on
frugivorous animals for dispersing their seeds, thereby providing an important ecological
function for seedling establishment. The interactions of frugivorous animals and fleshyfruited plants species are embedded within mutualistic interaction networks. Little
information, however, exists on how these interactions influence seedling establishment,
especially in species-rich tropical communities. Our aim with this study is to assess
relationships among abiotic factors (i.e. temperature, humidity and light), plant traits (i.e.
crop size, fruit morphology and pulp nutritional content), mutualistic interactions (i.e.
interaction strength and specialization level) and seedling establishment in Andean cloud
forests. We hypothesise that interaction strength and the degree of plant specialisation
directly affect seedling establishment. Accordingly, generalist plant species with a high
diversity of interactions are expected to have higher establishment success and may be
primarily be limited by abiotic filters. To address this hypothesis, we conducted this study
along an altitudinal gradient in the Colombian Andes (1800 to 2700 m) and set up ten
2
plots (100 x 20 m ), separated by 100 m elevation. After 120 hours of diurnal
observations per plot (1200 h in total) we compiled a network comprising 21 fleshyfruited plant species, 54 frugivorous bird and two mammal species. We also measured
the crop size, fruit morphology and pulp nutritional content of all consumed plant
species. We recorded temperature and humidity throughout the year in each plot with
data loggers, and solar irradiance with hemispherical photographs. Seedling
2
establishment was assessed in 600 subplots (1m , n = 60 subplots per plot). The
empirical data set obtained from our observations will allow us to estimate the relative
© The Authors & BOU, 2014 8 POSTER ABSTRACTS Birds in the entangled bank: advances in food webs theory and practice BOU Autumn Conference | Peterborough, UK | 19 November 2014 | Twitter #BOU2014 importance of biotic and abiotic factors for forest regeneration and to assess the impacts
of plant-frugivore networks in tropical forest.
AMF – Pollinator Networks: Can differing arbuscular mycorrhizal
fungal communities influence the structure of pollinator
communities, and does this vary according to plant traits?
PETER ORRELL
University of Hull, UK
[email protected]
Few studies have attempted to link below-ground species interactions with aboveground interactions. Arbuscular mycorrhizal fungi (AMF) have the potential to influence
plant architecture, development rate, volatile composition, nectar and pollen abundance
and quality, and a range of other factors besides the historical focus on increases in
biomass. These factors may influence the attraction of pollinators, and in turn shape the
ecological network structure of visiting pollinators and other animals. This experiment
examines the influence of varying AMF communities on pollinator visitation rates and
community structure in three genotypes of strawberry plants (Fragaria × ananassa);
Elsanta, Sonata, and Darselect. Four different AMF treatments were used; sterile
(control), a low diversity AMF community, a high diversity AMF community, and a
commercial inoculant. This study highlights the above-below ground interaction of AM
fungal and pollinator networks, as well as changes in the network structure due to the
impact of plant traits, through the use of different strawberry genotypes. With increasing
pressures on both declines in pollinator communities and the availability of
agrochemicals, research into this field may form part of a toolset for sustainable
increases in food security, as well as the promotion of important ecosystem services
provided by biodiversity.
© The Authors & BOU, 2014 9 POSTER ABSTRACTS Birds in the entangled bank: advances in food webs theory and practice BOU Autumn Conference | Peterborough, UK | 19 November 2014 | Twitter #BOU2014 High ecological specialization in hotspots of range-restricted
species for hummingbird communities across the Americas
JESPER SONNE
Center for Macroecology, Evolution and Climate, Department of Biology, University of
Copenhagen, Universitetsparken 15, DK-2100 Copenhagen, Denmark
[email protected]
Historical dynamics in species’ range size may influence local adaptation, speciationextinction events and spatial distributions of diversity. For instance, communities that
have experienced stable conditions through time may have preserved relatively
specialized interspecific associations and high proportions of range-restricted species.
Here, we analyzed data for specialization, range size distributions, and contemporary
climate and Quaternary climate stability for 48 plant-hummingbird mutualistic networks
distributed broadly across the New World, by use of structural equation models. Our
results supported a positive relationship between the proportion of range-restricted
hummingbird species and community-level specialization. Further, both variables were
associated with contemporary and Quaternary climate stability, but retained a tight
direct relationship after accounting for these. These results, augmented by the
observation that Quaternary climate stability only predicts specialization and proportion
of range-restricted species through one another, suggest that other aspects of ecological
stability, possibly related to deeper historical stability, increased specialization of
hummingbird-plant communities with many range-restricted species.
© The Authors & BOU, 2014 10