@article{HigginsFloresSchurr2008,
  author    = {Higgins, Steven I. and Flores, Olivier and Schurr, Frank Martin},
  title     = {Costs of persistence and the spread of competing seeders and sprouters},
  issn      = {0022-0477},
  doi       = {10.1111/j.1365-2745.2008.01391.x},
  year      = {2008},
  language  = {en}
}
@article{SchurrBondMidgleyetal.2005,
  author    = {Schurr, Frank Martin and Bond, William J. and Midgley, Guy F. and Higgins, Steven I.},
  title     = {A mechanistic model for secondary seed dispersal by wind and its experimental validation},
  issn      = {0022-0477},
  year      = {2005},
  abstract  = {1 Secondary seed dispersal by wind, the wind-driven movement of seeds along the ground surface, is an important dispersal mechanism for plant species in a range of environments. 2 We formulate a mechanistic model that describes how secondary dispersal by wind is affected by seed traits, wind conditions and obstacles to seed movement. The model simulates the movement paths of individual seeds and can be fully specified using independently measured parameters. 3 We develop an explicit version of the model that uses a spatially explicit representation of obstacle patterns, and also an aggregated version that uses probability distributions to model seed retention at obstacles and seed movement between obstacles. The aggregated version is computationally efficient and therefore suited to large-scale simulations. It provides a very good approximation of the explicit version (R-2 > 0.99) if initial seed positions vary randomly relative to the obstacle pattern. 4 To validate the model, we conducted a field experiment in which we released seeds of seven South African Proteaceae species that differ in seed size and morphology into an arena in which we systematically varied obstacle patterns. When parameterized with maximum likelihood estimates obtained from independent measurements, the explicit model version explained 70-77\% of the observed variation in the proportion of seeds dispersed over 25 m and 67- 69\% of the observed variation in the direction of seed dispersal. 5 The model tended to underestimate dispersal rates, possibly due to the omission of turbulence from the model, although this could also be explained by imprecise estimation of one model parameter (the aerodynamic roughness length). 6 Our analysis of the aggregated model predicts a unimodal relationship between the distance of secondary dispersal by wind and seed size. The model can also be used to identify species with the potential for long-distance seed transport by secondary wind dispersal. 7 The validated model expands the domain of mechanistic dispersal models, contributes to a functional understanding of seed dispersal, and provides a tool for predicting the distances that seeds move},
  language  = {en}
}
@article{HigginsClarkNathanetal.2003,
  author    = {Higgins, Steven I. and Clark, Stephen James and Nathan, Ran and Hovestadt, Thomas and Schurr, Frank Martin and Fragoso, Jose M. V. and Aguiar, Martin R. and Ribbens, Eric and Lavorel, Sandra},
  title     = {Forecasting plant migration rates : managing uncertainty for risk assessment},
  year      = {2003},
  abstract  = {1. Anthropogenic changes in the global climate are shifting the potential ranges of many plant species. 2. Changing climates will allow some species the opportunity to expand their range, others may experience a contraction in their potential range, while the current and future ranges of some species may not overlap. Our capacity to generalize about the threat these range shifts pose to plant diversity is limited by many sources of uncertainty. 3. In this paper we summarize sources of uncertainty for migration forecasts and suggest a research protocol for making forecasts in the context of uncertainty.},
  language  = {en}
}
@article{SarmentoJeltschThuilleretal.2013,
  author    = {Sarmento, Juliano Sarmento and Jeltsch, Florian and Thuiller, Wilfried and Higgins, Steven and Midgley, Guy F. and Rebelo, Anthony G. and Rouget, Mathieu and Schurr, Frank Martin},
  title     = {Impacts of past habitat loss and future climate change on the range dynamics of South African Proteaceae},
  series = {Diversity \& distributions : a journal of biological invasions and biodiversity},
  volume    = {19},
  journal   = {Diversity \& distributions : a journal of biological invasions and biodiversity},
  number    = {4},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {1366-9516},
  doi       = {10.1111/ddi.12011},
  pages     = {363 -- 376},
  year      = {2013},
  abstract  = {Aim To assess how habitat loss and climate change interact in affecting the range dynamics of species and to quantify how predicted range dynamics depend on demographic properties of species and the severity of environmental change. Location South African Cape Floristic Region. Methods We use data-driven demographic models to assess the impacts of past habitat loss and future climate change on range size, range filing and abundances of eight species of woody plants (Proteaceae). The species-specific models employ a hybrid approach that simulates population dynamics and long-distance dispersal on top of expected spatio-temporal dynamics of suitable habitat. Results Climate change was mainly predicted to reduce range size and range filling (because of a combination of strong habitat shifts with low migration ability). In contrast, habitat loss mostly decreased mean local abundance. For most species and response measures, the combination of habitat loss and climate change had the most severe effect. Yet, this combined effect was mostly smaller than expected from adding or multiplying effects of the individual environmental drivers. This seems to be because climate change shifts suitable habitats to regions less affected by habitat loss. Interspecific variation in range size responses depended mostly on the severity of environmental change, whereas responses in range filling and local abundance depended mostly on demographic properties of species. While most surviving populations concentrated in areas that remain climatically suitable, refugia for multiple species were overestimated by simply overlying habitat models and ignoring demography. Main conclusions Demographic models of range dynamics can simultaneously predict the response of range size, abundance and range filling to multiple drivers of environmental change. Demographic knowledge is particularly needed to predict abundance responses and to identify areas that can serve as biodiversity refugia under climate change. These findings highlight the need for data-driven, demographic assessments in conservation biogeography.},
  language  = {en}
}
@article{SvenningGravelHoltetal.2014,
  author    = {Svenning, Jens-Christian and Gravel, Dominique and Holt, Robert D. and Schurr, Frank Martin and Thuiller, Wilfried and Muenkemueller, Tamara and Schiffers, Katja H. and Dullinger, Stefan and Edwards, Thomas C. and Hickler, Thomas and Higgins, Steven I. and Nabel, Julia E. M. S. and Pagel, J{\"o}rn and Normand, Signe},
  title     = {The influence of interspecific interactions on species range expansion rates},
  series = {Ecography : pattern and diversity in ecology ; research papers forum},
  volume    = {37},
  journal   = {Ecography : pattern and diversity in ecology ; research papers forum},
  number    = {12},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {0906-7590},
  doi       = {10.1111/j.1600-0587.2013.00574.x},
  pages     = {1198 -- 1209},
  year      = {2014},
  language  = {en}
}