Browsing by Author "Jaime Collazo, Chair"
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- Abundance and Breeding Productivity of Resident Avian Species in Guanica State Forest.(2011-10-24) Kornegay, Mary; Jaime Collazo, Chair; Steve Dinsmore, External; James Gilliam, Member; Theodore Simons, Member
- Avian Response to Shade-layer Restoration in Coffee Plantations in Puerto Rico.(2017-08-10) Irizarry, Amarilys D; Jaime Collazo, Chair; Jamian Pacifici, Member; Brian Reich, Minor
- Characterizing Metabolic Responses of Eleutherodactylus Frogs in Puerto Rico to Different Thermal Treatments: Implications for Conservation and Management.(2023-03-20) Chaparro, Rafael; Jaime Collazo, Chair; Adam Terando, Member; Eloy Martinez, External; Jamian Pacifici, Member
- Demographic rates and Prioritization of Habitat for Conservation for Painted Buntings in North Carolina.(2016-12-06) Yirka, Liani Marie; Jaime Collazo, Chair; Brian O'Shea, Technical Consultant; Nicholas Haddad, Member; Jamian Pacifici, Member
- Ecological and Political Implications of Conversion from Shade to Sun Coffee in Puerto Rico(2002-01-10) Borkhataria, Rena Rebecca; Jaime Collazo, Chair; Martha Groom, Member; Marcia Gumpertz, Member; Harold Heatwole, Member; Robert Rice, MemberRecent studies have shown that biodiversity is greater in shaded plantations than in sun coffee plantations, yet many farmers are converting to sun coffee varieties to increase short-term yields or to gain access to economic incentives. Through conversion, ecosystem complexity may be reduced and ecological services rendered by inhabitants may be lost. I attempted to quantify differences in abundances and diversity of predators in sun and shade coffee plantations in Puerto Rico and to gain insight into the ecological services they might provide. I also interviewed coffee farmers to determine the factors influencing conversion to sun coffee in Puerto Rico and to examine their attitudes toward the conservation of wildlife. Avian abundances were significantly higher in shaded coffee than in sun (p = 0.01) as were the number of species (p = 0.09). Avian species that were significantly more abundant in shaded coffee tended to be insectivorous, whereas those in sun coffee were granivorous. Lizard abundances (all species combined) did not differ significantly between plantations types, but Anolis stratulus was more abundant in sun plantations and A. gundlachi and A. evermanni were present only in shaded plantations. Insect abundances (all species combined) were significantly higher in shaded coffee (p = 0.02). I used exclosures in a shaded coffee plantation to examine the effects of vertebrate predators on the arthropods associated with coffee, in particular the coffee leaf miner (Leucoptera coffeela) and the flatid planthopper Petrusa epilepsis, in a shaded coffee plantation in Puerto Rico. Treatments included exclusion of birds, lizards, birds and lizards, and no exclusion. I found that birds had a significant effect on the abundance of Petrusa epilepsis and on insects > 5 mm in length. Combined insect species abundance as well as abundance of insects 2-5 mm and 5-10 mm varied significantly by treatment and removal of both birds and lizards had a larger effect than the removal of either taxa alone. Vertebrate predators exerted little influence over the coffee leaf miner, nor did they appear to appear with the leaf miner's natural enemies, a complex of parasitoid wasps. In the survey of 100 coffee farmers, I found that sun coffee was substantially more prevalent than shaded coffee, both in number of farms and in land area devoted to its production. The average sun coffee plantation was significantly larger than the average shaded plantation (p = 0.02). Reasons for conversion from shade to sun coffee included higher yields, recommendations by agronomists, and incentives from the government. Farmers placed high conservation value on species that are rare or provide services to humans. Vertebrate insectivores were more diverse and abundant in shaded coffee and may provide a service to farmers by depressing total insect numbers and preventing outbreaks of the planthopper Petrusa epilepsis. Furthermore, they did not interfere with parasitism of the coffee leaf miner by parasitoid wasps. I conclude that governmental incentives for shaded coffee have a high probability of success, since coffee growers are highly dependent upon assistance from the government.
- Habitat Suitability for Eleutherodactylus Frogs in Puerto Rico: Indexing Occupancy, Abundance and Reproduction to Climatic and Habitat Characteristics.(2019-08-19) Rivera-Burgos, Ana Cecilia; Jaime Collazo, Chair; Jamian Pacifici, Member; Adam Terando, Member
- Habitat Use and Survival of Eastern Cottontails (Sylvilagus floridanus) on Christmas Tree Farms, and the Utility of Expert Knowledge in Informing Management Decisions on Human-modified Landscapes.(2016-08-10) Dziwulski, Kara Elizabeth; Jaime Collazo, Chair; Luther Mills, Member; David Cobb, Member; Brian Reich, Minor
- Improving Inferences about the Occupancy Dynamics of Forest-Dwelling Passerines in the US Gulf Coast Region Using Multiple Land Cover Data Sets(2019-05-10) Page, Jessica Hope; Jaime Collazo, Chair; Jamian Pacifici, Member; Alexa McKerrow, Member
- King Rail (Rallus elegans) Occupancy, Reproductive Activity and Success in Fire Managed Coastal Marshes of North Carolina and Virginia.(2011-06-17) Rogers, Samantha; Jaime Collazo, Chair; Theodore Simons, Member; Thomas Wentworth, Minor
- Occupancy and Abundance of Eleutherodactylus Frogs in Coffee Agroecosystems and Along an Elevational Gradient in the Mountains of Southwestern Puerto Rico(2016-04-15) Dowdy, Kelen Eliza; Jaime Collazo, Chair; Jamian Pacifici, Member; Brian Reich, Minor
- Patch dynamics and Permeability of Fragmented Habitat in Southwestern Puerto Rico.(2012-10-26) Irizarry, Julissa Ivelisse; Jaime Collazo, Chair; Nicholas Haddad, Member; Theodore Simons, Member
- Population Characteristics and Parasitology of the American Eel in Puerto Rico.(2022-10-31) Torres Molinari, Ambar; Jaime Collazo, Chair; Jamian Pacifici, Minor; Luis Ramirez-Ulate, Member; Augustin C. Engman, External; Andrew Dolloff, External
- Shorebird Numbers, Distribution and Wetland Connectivity Among Coastal Wetlands in Southwestern Puerto Rico.(2015-10-13) Parks, Morgan A; Jaime Collazo, Chair; Jamian Pacifici, Member; Brian Reich, Member
- Status Assessment of Henslow's Sparrows in North Carolina: a Multidisciplinary Framework for Conservation.(2024-08-30) Nastase, Emily Annette; Jaime Collazo, Chair; Jamian Pacifici, Minor; Alexa McKerrow, Member; Nicholas Mason, External; Nathan Hostetter, Member
