Projects | GOnormandie

Burning Bridges: Early eradication and management of invasive species

Mon, 27 May 2024 00:00:00 +0000

Early intervention of invasive species is often cited as the best course of action because the costs from long-term management and damages caused by the species are less when it is less abundant and/or constrained to a small area. Literature suggests that there is a point in the invasion curve after which management becomes too expensive, and eradication unfeasible (hereon referred to as “critical point”). Interventions before this critical point are referred to as early. Nonetheless, the definition of early is not clear. In fact, given the complexities and circumstantial nature of biological invasions, this critical point is not static. Here, we propose a mathematical description of this critical point by arguing that it is influenced by time, population dynamics, and the budgetary constraints of the management program. We use computer simulations to evaluate the robustness of this definition to a more stochastic model. Identifying the critical point in the invasion process before which intervention can be classified as early could aid policy makers and managers to take informed decisions on how to allocate resources given the population dynamics of the invasive population and the budgetary constraints of the management program.

NOTE: This is not meant to be a scientific report, but rather a friendly account of my research project. For more technical details or the scientific report, reach out to me and I will gladly provide the information.

Feral Cats in Puerto Rico

Mon, 27 Nov 2023 00:00:00 +0000

The domestic cat has been banned from a number of islands in the world. For example, they were eradicated from several outlying islands of New Zealand, as part of conservation programs that aimed to protect and/or restore native populations of birds and mammals. In Australia they are having open seasons to hunt cats to lower the population size. Both countries are only looking to protect their native species, since the negative effects of free roaming cats in native fauna have been demonstrated in several meta analyses around the world, especially on islands. Puerto Rico has a high number of feral cats, still a reliable estimate of the population size has not been done. We used mark-recapture techniques in three municipalities of Puerto Rico to estimate feral cat population size in the area. An estimation of the population size of cats is the first step towards understanding the possible effects of the population on the native fauna and public health of the archipelago, and the development of management strategies.

Host suitability for germination differs from that of later stages of development in a rare epiphytic orchid

Mon, 27 Nov 2023 00:00:00 +0000

We explore phorophyte suitability for germination and establishment of the epiphytic orchid, Psychilis kraenzlinii. We found that the orchid grows on a subset of the available tree species and shows pref-erence for the endemic Machaonia portoricensis (Rubiaceae). The orchid preferred trees with smoother bark, high water holding capacity and low water retention capacity. Microclimatic conditions under which embryos began pre-germination stages mirrored that of the adult orchid, but germination did not, suggesting that suit-able germination sites are not necessarily the best sites for later stages of development.

Of Toads and May beetles

Mon, 27 Nov 2023 00:00:00 +0000

Scientists in Puerto Rico introduced the cane toad (Rhinella marina) as a biocontrol of Phyllophaga sp. (may beetle) infestation in sugar cane plantations in the early 1900s. Although the may beetle problem receded, scientist question whether this was thanks to the toad. In 1984, Freeland, W. J., stated that the decline of the beetle population in Puerto Rico was due to extreme wet and dry seasons between 1930-1936, and not the because of the introduction of the toad. Given the lack of data, we cannot evaluate if the introduction of R. marina was effective against the population of may beetles in Puerto Rico. Nonetheless, historical data of precipitation in Puerto Rico can be used to evaluate if during these years Puerto Rico had extreme wet and dry seasons.

Speciation and Pollination of Ghost Orchids in La Hispaniola

Mon, 27 Nov 2023 00:00:00 +0000

Morphological differences in flowers of Dendrophylax sp. in the Dominican Republic suggest speciation and exploitation of different pollinators. In collaboration with the National Botanical Garden Dr. Rafael María Moscoso in the Dominican Republic, and peers from the University of Illinois, we are conducting research to elucidate the taxonomy of Dendrophylax in La Hispaniola.

Morphological data of the flowers in different populations are being measured to proof that the differences that were previously observed are statistically significant. Since flower morphology is related to pollinators, we hypothesize that floral fragrance composition will also differ among populations, because different pollinators are being targeted. Therefore, we are conducting floral fragrance analysis from the different populations using GC-MS analysis. The pollinators of Dendrophylax in La Hispaniola are unknown. Nonetheless, given morphology and fragrance of the flower, we hypothesized that the pollinator is a hawkmoth. This is supported also by the fact that D. lindenii in Florida, USA is pollinated by hawkmoths. We are using light traps to try and catch a possible pollinator. To go even further on the determination of differentiation and speciation, we are collecting tissue form different species and populations to run DNA analysis and develop the phylogeny for Dendrophylax in La Hispaniola.

Geospatial Explorers

Mon, 01 Jan 0001 00:00:00 +0000

LUQ-LTER Data Jam

Mon, 01 Jan 0001 00:00:00 +0000