Faculty Research and Publications
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Item Nest Reutilization by Polistes metricus (Hymenoptera: Vespidae) and Possible Limitations of Multiple Foundress Associations by Parasitoids(1976-01) Starr, C. K.The reutilization is reported of an old nest by three female wasps, and the condition of the nest and its constituent cells, is recorded at the end of the season. Larvae of pyralid genus Chalcoela are believed to have been a major cause of the nest's apparent low productivity. It is postulated that strong parasitoid pressure by Chalcoela is a selective factor against nest-founding by associated multiple queens in some North American species of Polistes.Item Annotated List of Spider Families (Araneida) of Trinidad and Tobago(Living World, J. Trinidad and Tobago Field Naturalists’ Club, 2003) Sewlal, Jo-Anne N; Cutler, BruceThe spider families of the neotropical islands of Trinidad and Tobago are reviewed. Forty one families are definitely recorded, while an additional 12 families are considered as likely, based on their presence in the nearby South American mainland. Biological and recognition characters are noted for most of the families.Item Observations of nest and colony structure of the neotropical ant Dolichoderus attelaboides (Formicidae: Dolichoderinae)(Living World, J. Trinidad and Tobago Field Naturalists’ Club, 2004) Sewlal, Jo-Anne N; Starr, Christopher KItem Observations of nest and colony structure of the neotropical ant Dolichoderus attelaboides (Formicidae: Dolichoderinae)(Living World, J. Trinidad and Tobago Field Naturalists’ Club, 2004) Sewlal, Jo-Anne N; Starr, Christopher KItem An observation of nest relocation in the ant Cephalotes atratus.(Living World, J. Trinidad and Tobago Field Naturalists’ Club, 2004) Starr, Christopher K; Sewlal, Jo-Anne NItem An observation of nest relocation in the ant Cephalotes atratus(Living World, J. Trinidad and Tobago Field Naturalists’ Club, 2004) Starr, Christopher K; Sewlal, Jo-Anne NItem Heuristic Constraint-Path Routing Decision System(IEEE Computer Society, 2005-05-18) Sivakumar, Shyamala; Phillips, William J.; Robertson, William; Goodridge, WayneHeuristic QoS algorithms under strict constraints perform poorly in terms of finding a path that is suitable for a user?s QoS needs - the multiple constraint path problem (MCP). Exact QoS algorithms, on the other hand, guarantee that a path satisfying user needs would be found and o..er a more realistic approach for solving the MCP problem in view of the fact that the NP-complete character of graphs are not common in real networks. This fact has driven approaches like the SAMCRA and A*prune algorithms. However, these algorithms still have very high running times relative to heuristic approaches. When QoS routing algorithms are used in online Tra..c Engineering (TE) environments it may be necessary to route thousands of traffic flows each minute. Exact algorithms simply cannot work in such environments. We propose a heuristic algorithm that is suitable for working in an online TE environment. Simulations show that this algorithm produce high success rates in terms of finding suitable constraint paths for user flows while at the same time having execution times comparable to another heuristic based algorithms.Item Web height as a niche separator in two orb-weaving spiders.(Living World, J. Trinidad and Tobago Field Naturalists’ Club, 2006) Starr, Christopher K; Sewlal, Jo-Anne NItem Karyotype and male reproductive system in Arachnocoris trinitatus Bergroth. First data on the tribe Arachnocorini (Heteroptera: Nabidae: Nabinae). Folia Biologica (Kraków)(Folia biologica (Kraków), 2007) Kuznetsova, Valentina G.; Grozeva, Snejana; Sewlal, Jo-Anne N; Nokkala, SeppoAs an extension of the ongoing cytogenetic studies of the bug family Nabidae (Heteroptera:Cimicomorpha), the first evidence for the tribe Arachnocorini (the subfamily Nabinae), with reference to the Trinidad endemic, Arachnocoris trinitatus Bergroth, is provided. This is an attempt to gain a better insight into the evolution, systematics and within-family relationships of the family Nabidae. The studies were conducted using a number of cytogenetic techniques. The male karyotype (chromosome number and size; sex chromosome system; NOR location; C-heterochromatin amount, distribution and characterization in terms of the presence of AT-rich and GC-rich DNA), and male meiosis with particular emphasis on the behavior of the sex chromosomes in metaphase II are described. Also investigated are the male and female internal reproductive organs with special reference to the number of follicles in a testis and the number of ovarioles in an ovary. A. trinitatus was found to display a number of characters differentiating it from all hitherto studied nabid species placed in the tribe Nabini of the subfamily Nabinae, and in the tribe Prostemmatini of the subfamily Prostemmatinae. Among these characters are chromosome number 2n = 12 (10 + XY), the lowest within the family, nucleolus organizer regions (NORs)situated on the autosomes rather than on the sex chromosomes as is the case in other nabid species, and testes composed of 3 follicles but not of 7 as in other nabids. All the data obtained suggest many transformations during the evolution of A. trinitatus.Item Preliminary Survey for Spiders on Nevis, West Indies(Living World, J. Trinidad and Tobago Field Naturalists’ Club, 2007) Sewlal, Jo-Anne N; Starr, Christopher KItem Addendum - Four more Trinidadian Spider (Araneida) families(Living World, J. Trinidad and Tobago Field Naturalists’ Club, 2007) Sewlal, Jo-Anne N; Alayón, GiraldoItem Observations of the insect Arachnocoris trinitatus (Heteroptera: Nabidae) as an inquiline in the webs of the spider Mesabolivar aurantiacus (Araneae: Pholcidae)(Caribbean Journal of Science, 2008) Sewlal, Jo-Anne N; Starr, Christopher K—The pholcid spider Mesabolivar aurantiacus (Mello-Leitão 1930) is common in forests of Trinidad, West Indies. Its webs are often found to contain the nabid bug Arachnocoris trinitatis (Bergroth 1916). In a lowland forest in August-September 2003 (wet season) we censused 81 M. aurantiacus webs for occupancy by the spider and the insect. A. trinitatis showed no significant preference for webs occupied by either juvenile or adult spiders. However, it showed a preference for empty webs, suggesting that it utilizes these as a ready-made preycapture device, and possibly as a site for finding mates.Item Preliminary Survey for Spiders on St. Kitts, West Indies with Comparative Notes on Nevis.(Living World, J. Trinidad and Tobago Field Naturalists’ Club, 2008) Sewlal, Jo-Anne NItem New Record of Pholcid genera for Lesser Antilles, West Indies.(Living World, J. Trinidad and Tobago Field Naturalists’ Club, 2008) Sewlal, Jo-Anne N; Starr, Christopher KItem Preliminary Survey for Spiders on Antigua, West Indies.(The College of The Bahamas Research Journal, 2009) Sewlal, Jo-Anne NSpiders have a worldwide distribution that comprises all land environments except at the polar extremes. There are now 40,700 named, described species of spiders (Platnick, 2009), thought to represent about one-fifth of the true total. On a faunistic level, the spiders of some regions are reasonably well known, but this is far from the case in the New World tropics, including the West Indies. At present, we have species-level surveys for Cuba (Alayón, 1995), Barbados (Bryant, 1923; Alayón and Horrocks, 2004), St. Vincent and the Grenadines (Simon, 1894; de Silva, Horrocks and Alayón, 2006), Anguilla (Sewlal and Starr, 2006), Nevis (Sewlal and Starr, 2007), St. Kitts (Sewlal, 2008) and Grenada (Sewlal, 2009a), and a familylevel list for Trinidad (Cutler, 2005, Sewlal and Cutler, 2003, Sewlal and Alayón, 2007, Sewlal, 2009b). Additional information on the family Pholcidae of some of the Lesser Antilles is provided by Sewlal and Starr (2008). The present short communication serves to expand on Bryant’s (1923) list of 23 species from Antigua and to treat the species distribution on the island with respect to habitats. This survey adds 18 species and 11 families to the list compiled by Bryant (1923).Item Two Additional Spider (Arachnida:Araneida) Families for Trinidad and Tobago(Living World, J. Trinidad and Tobago Field Naturalists’ Club, 2009) Sewlal, Jo-Anne NItem Observations of the insect Arachnocoris trinitatus (Heteroptera: Nabidae) as an inquiline of the spider Coryssocnemis simla (Araneae: Pholcidae) in West Indies.(Zoosystematica Rossica., 2009) Sewlal, Jo-Anne N; Starr, Christopher KThe nabid bug Arachnocoris trinitatus (Bergroth, 1916) is often found in webs of the pholcid spider Coryssocnemis simla Huber, 2000. Thirty-one webs of C. simla were checked for occupancy by the spider and the insect in April 2008 in a deciduous seasonal forest in Trinidad, West Indies. Arachnocoris trinitatus showed no significant preference either for webs occupied by juvenile versus adult spiders, or for empty webs versus those occupied by C. simla.Item A Preliminary Survey for Spiders on Grenada, West Indies(Living World, J. Trinidad and Tobago Field Naturalists’ Club, 2009) Sewlal, Jo-Anne NDuring a two-week period in 2008, a wide variety of habitats on the island of Grenada, West Indies were surveyed for the presence of spiders. Contrary to the results of previous surveys in the Eastern Caribbean, Grenada exhibited a higher species richness in natural habitats. Members of the families Araneidae and Tetragnathidae comprised of almost half the species found. Some 12 localities were surveyed from 11 habitats, including six man-made habitats. Ten families representing 22 species were collected.Item Getting to know our sea turtles(Tobago News, 2009-07-10) Sewlal, Jo-Anne