Biology subjects

Ponti, L.

Publications and source records attributed to Ponti, L..

3 recordsLinked to original sources

bioRxiv2026

Re-invasion of the New World screwworm in Central and North America: comparative analysis of three SIT eradication efforts

In sharp contrast to biological control that seeks control of pests below economic levels, eradication programs seek total extermination of pest species. However, eradication programs are often undertaken without knowledge of the pests potential geographic distribution and relative abundance (i.e., geographic risk assessment), often leading to eradication efforts conducted across areas much greater than the potential permanent range of the target species. To demonstrate this, we review eradication efforts against the tropical New World screwworm (Cochliomyia hominivorax) in the SE USA and Mexico, the exotic sub-tropical tephritid Mediterranean fruit fly (Ceratitis capitata, medfly) in California, and the exotic tropical pink bollworm (Pectinophora gossypiella, PBW) in the SW USA. We use mechanistic physiologically based demographic models (PBDMs) that are physiologically based time varying life tables to decompose the systems and to assess risk under extant and climate change scenarios.

ecology↗

bioRxiv2025

Ex ante analyses can predict natural enemy efficacy in biological control

The success rate of biological control programs against invasive species is low because the efficacy of released natural enemies is unknown. Deconstruction of the successful biological control of the highly destructive cassava mealybug (CM) and cassava green mite (CGM) in Africa is used to show how ex ante pre-release analyses of natural enemies can increase the success rate. A meta-population tri-trophic physiologically based demographic model (PBDM) of the cassava system accurately predicted the weather-driven daily dynamics of cassava, CM, CGM, and their introduced natural enemies across the ecological zones of Africa. Marginal analyses of the simulation data enabled parsing the differing contributions of two exotic parasitoids and a fungal pathogen in the control of CM, and the contributions of two mite predators, local pathogens and rainfall mortality in the control of CGM. The contribution of each natural enemy to the [~]95% recovery of cassava yields is estimated. The results show ex ante analyses of prospective natural enemies using well parameterized PBDMs can predict natural enemy prerelease efficacy across vast geographic areas and increase the success rate of biological control programs. Ex ante analyses can also explain whether biological control is a viable option (e.g., Cure et al. 2020).

ecology↗

bioRxiv2024

Physiologically based demographic model/GIS analyses of thirteen invasive species in Africa: why the biology matters

Globally, research and policy groups often lack the expertise to develop appropriate models to analyze agroecological and invasive species problems holistically to inform management and quarantine policy development under extant and climate change over wide geographic landscapes. Off-the-shelf species distribution models (SDM) correlate weather and other variables to records of species presence and have become the mainstay for predicting the geographic distribution and favorability of invasive species (Elith 2017). However, SDM analyses lack the capacity to examine the underpinning dynamics of agroecosystems required to inform policy and develop management strategies. We propose that age-structured physiologically based demographic models (PBDMs) can solve important aspects of this challenge as they can be used to examine prospectively species dynamics locally as well as their potential geographic distribution and relative abundance across vast areas independent of presence records. PBDMs fall under the ambit of time-varying life tables (TVLTs; cf. Gilbert et al. 1976) and capture the weather driven biology, dynamics, and interactions of species, and can be used to examine the system from the perspective of any of the interacting species. Here, we use the PBDM structure to examine the dynamics across Africa of thirteen invasive species from various taxa having diverse biology and trophic interactions (see Gutierrez 1996, Gutierrez and Ponti 2013a). PBDMs are perceived to be difficult to develop, hence the raison detre is to show this is not the case and illustrate their utility invasive and endemic agricultural and medical/veterinary pest species at the local and the large geographic scale of Africa. We note that PBDMs provide a structure for continued model improvements. The development of open access software is proposed to facilitate PBDM development by non-experts emphasizing the crucial role of sound biological data on species responses to weather and to other species in a multi-trophic, interactions, and provide a guide for collecting the appropriate biological data. While the emphasis is on plant/arthropod interactions, models of diseases can be accommodated. The Supplemental Materials summarizes a large array of heritage PBDMs reported in the literature based on the methods outline herein, noting that the same model structure can be used to analyze and manage non pest species.

ecology↗