Potential study species

The reproductive biology of Cactaceae is not well known – only approximately 2% of the 2000 or so species have been studied (Mandujano et al, 2010). Consequently, how they interact with neighbouring plants of different species for pollinators or what this means in a community context are both virtually unknown. In one of the few published experiments that explicitly tested these interactions, researchers focused on the highly invasive prickly-pear Opuntia stricta in coastal shrublands in Catalonia (Bartomeus 2008). Cacti in the Opuntia genus are primarily bee-pollinated; they have large, colourful bowl-shaped flowers and many species are rich in pollen and nectar (Mandujano et al, 2010), suggesting they are very attractive to pollinators. Plants that exhibit these characteristics can interact with other plants in two notable ways for pollinators – they may act as a magnet plant, increasing local abundances of shared pollinators and thus facilitating the pollination of their neighbours, or conversely, they may steal pollinators and reduce the fitness of their neighbours.

To determine the effects of the invasion on the native plant community, the researchers created plant-pollinator interaction networks for both invaded and uninvaded sites. They found that O. stricta acted as a super-generalist in its new range. It was visited by 31% of the insect taxa in the invaded sites and was outcompeting native plants for pollination services. Within the same study, they found that Carpobrotus, an invasive succulent, had the opposite interaction with the surrounding plant community; it facilitated the pollination of the native plants in the system. This highlights the species-specific and context-dependent aspects of these interactions. There are a few species of Opuntia common in the Mojave Desert, and I hope to discover if and how they are interacting with other plants, particularly shrubs and their annual understory.

Attribution Stan Shebs [GFDL (http://www.gnu.org/copyleft/fdl.html), CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0) or CC BY-SA 2.5 (http://creativecommons.org/licenses/by-sa/2.5)], via Wikimedia Commons

Bartomeus, I., Vilà, M., & Santamaría, L. (2008). Contrasting effects of invasive plants in plant–pollinator networks. Oecologia, 155(4), 761-770.

del Carmen Mandujano, M., Carrillo-Angeles, I., Martínez-Peralta, C., & Golubov, J. (2010). Reproductive biology of Cactaceae. In Desert plants (pp. 197-230). Springer Berlin Heidelberg.

#ESA2015 Organized Session: Implications of positive interaction studies to the future of ecological research

We would like to invite you to the ESA 2015 session OOS 37 (quite a few of us from the lab will be in attendance).

Implications of positive interaction studies to the future of ecological

research. The session is on Wednesday, August 12th from 8:00-11:30am.


The goal of this session is to highlight the current state of

facilitation research and describe the future projections including

available gaps in the literature. Broadly, this session provides a

synthesis of positive interaction studies across different ecosystems with

topics ranging from niche expansion, coexistence, evolutionary adaptation,

and global change. This set of studies showcase the growing importance of

positive interactions for ecological processes and biodiversity

coexistence. We also guarantee that it will be entirely entertaining. We

will be on social media to share and explore questions in real time. We are

encouraging presenters to share in advance as well.





8:00 AM – A role for soil microbial communities in plant-plant facilitation

Cristina Armas, Consejo Superior de Investigaciones Científicas; Yudi M.

Lozano, Consejo Superior de Investigaciones Científicas; Sara Hortal,

University of Western Sydney; Susana Rodríguez-Echeverría, Centre for

Functional Ecology; Francisco I. Pugnaire, Consejo Superior de

Investigaciones Científicas

8:20 AM – Positive interactions expand habitat use and the realized niches

of sympatric species

Sinead M. Crotty, Brown University; Mark D. Bertness, Brown University

8:40 AM – Facilitation in plant communities: Driver of evolutionary


Christian Smit, University of Groningen

9:00 AM – The future of gradient studies in examining plant-plant

interactions for the next 100 years

Chris Lortie, York University

9:20 AM – The consequences of plant–plant interactions at the community

level: A niche-based approach

Christian Schöb, University of Zurich; Sara Hortal, University of Western

Sydney; Alison J. Karley, The James Hutton Institute; Luna Morcillo,

Universitat d’Alacant; Andrian C. Newton, The James Hutton Institute; Robin

J. Pakeman, The James Hutton Institute; Jeff R. Powell, University of

Western Sydney; Ian Anderson, University of Western Sydney; Rob W. Brooker,

The James Hutton Institute

9:40 AM – Break

9:50 AM – The competition cascade: Indirect facilitation emerges as a key

driver of species richness under neutral, niche or individual difference

Eliot J. B. McIntire, Natural Resources Canada

10:10 AM – Positive species interactions and climate change at global scales

Qiang He, Duke University; Brian R. Silliman, Duke University

The session is on room 314 of the Baltimore Convention Center. We hope to

see you there!