Browsing by Author "Silliman, BR"

Now showing 1 - 5 of 5

Open Access
Crab predation by the San Salvador rock iguana (Cyclura rileyi)
(Herpetological Bulletin, 2015-01-01) Gaskins, LC; Silliman, BR
Open Access
Facilitation shifts paradigms and can amplify coastal Restoration efforts
(Proceedings of the National Academy of Sciences of the United States of America, 2015-11-17) Silliman, BR; Schrack, E; He, Q; Cope, R; Santoni, A; van der Heide, T; Jacobi, R; Jacobi, M; van de Koppel, J
Restoration has been elevated as an important strategy to reverse the decline of coastal wetlands worldwide. Current practice in restoration science emphasizes minimizing competition between outplanted propagules to maximize planting success. This paradigm persists despite the fact that foundational theory in ecology demonstrates that positive species interactions are key to organism success under high physical stress, such as recolonization of bare substrate. As evidence of how entrenched this restoration paradigm is, our survey of 25 restoration organizations in 14 states in the United States revealed that >95% of these agencies assume minimizing negative interactions (i.e., competition) between outplants will maximize propagule growth. Restoration experiments in both Western and Eastern Atlantic salt marshes demonstrate, however, that a simple change in planting configuration (placing propagules next to, rather than at a distance from, each other) results in harnessing facilitation and increased yields by 107% on average. Thus, small adjustments in restoration design may catalyze untapped positive species interactions, resulting in significantly higher restoration success with no added cost. As positive interactions between organisms commonly occur in coastal ecosystems (especially in more physically stressful areas like uncolonized substrate) and conservation resources are limited, transformation of the coastal restoration paradigm to incorporate facilitation theory may enhance conservation efforts, shoreline defense, and provisioning of ecosystem services such as fisheries production.
Metadata only
Grazing scar characteristics impact degree of fungal facilitation in spartina alterniflora leaves in a south american salt marsh
(Brazilian Archives of Biology and Technology, 2015-01-01) Freitas, RF; Schrack, EC; Sieg, RD; Silliman, BR; Costa, CSB
Grazing scars of burrowing crabs and Hemiptera insects were simulated on leaves of the salt marsh grass Spartina alterniflora. Simulations of crab feeding generated two-fold higher fungal (ergosterol) content in leaves in comparison to that generated by insect scar simulations (1.26 ± 0.55 and 0.57 ± 0.25 μg per cm2, respectively). This study provided evidence that herbivory could facilitate microbial infection by fungi in dominant South American salt marsh plants and indicated that specific feeding mechanisms used by different herbivores might differentially impact the strength of this interaction.
Open Access
Livestock as a potential biological control agent for an invasive wetland plant
(PeerJ, 2014) Silliman, BR; Mozdzer, T; Angelini, C; Brundage, JE; Esselink, P; Bakker, JP; Gedan, KB; van de Koppel, J; Baldwin, AH
Invasive species threaten biodiversity and incur costs exceeding billions of US$. Eradication efforts, however, are nearly always unsuccessful. Throughout much of North America, land managers have used expensive, and ultimately ineffective, techniques to combat invasive Phragmites australis in marshes. Here, we reveal that Phragmites may potentially be controlled by employing an affordable measure from its native European range: livestock grazing. Experimental field tests demonstrate that rotational goat grazing (where goats have no choice but to graze Phragmites) can reduce Phragmites cover from 100 to 20% and that cows and horses also readily consume this plant. These results, combined with the fact that Europeans have suppressed Phragmites through seasonal livestock grazing for 6,000 years, suggest Phragmites management can shift to include more economical and effective top-down control strategies. More generally, these findings support an emerging paradigm shift in conservation from high-cost eradication to economically sustainable control of dominant invasive species.
Open Access
Megafauna in Salt Marshes
(Frontiers in Marine Science) Gaskins, LC; Paxton, AB; Silliman, BR