Pacific Science, Volume 62, Number 2, 2008

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    Association Affairs
    (Honolulu, University of Hawaii Press, 2008-04)
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    Additional Marine Benthic Algae from Howland and Baker Islands, Central Pacific.
    (Honolulu, University of Hawaii Press, 2008-04) Tsuda, Roy T. ; Vroom, Peter S. ; Abbott, Isabella A. ; Fisher, Jack R. ; Foster, Kevin B.
    Marine benthic algae from Howland Island and Baker Island were identified from collections made during earlier expeditions in 1924, 1935, and 1964, and during five separate expeditions between 1998 and 2004. Eightynine (six blue-green algae, 53 red algae, five brown algae, and 25 green algae) of the 99 species represent new records for the two islands. Forty-seven and 86 species are documented with voucher specimens from Howland Island and Baker Island, respectively. This study increases the total number of benthic marine algal species from the two islands to 104 species. A similar number (107 species) was previously reported from the nearby low coral islands in the Phoenix Group located 400 km to the southwest. Only 38% (39 of 104 species) of the algal species from Howland Island and Baker Island are reported from the Phoenix Group. The presence of Udotea palmetta Decaisne on Baker Island is of interest because the record is the first for this green algal genus in the central Pacific region.
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    Role of Pro-Thrombolites in the Geomorphology of a Coastal Lagoon.
    (Honolulu, University of Hawaii Press, 2008-04) Siqueiros-Beltrones, D.A.
    Thrombolites are lithified biosedimentary structures generated by entrapment, precipitation, and binding of sediments promoted by growth and metabolic activity of cyanobacteria. Beaches of the coastal lagoon known as Ensenada de La Paz in Baja California Sur, Me´xico, are bordered by sedimentary formations of cyanobacterial origin identified as pro-thrombolites (incipient thrombolites) that represent a first record for the region and Me´xico. Observed thrombolithic structures show grains of varied sizes embedded within a fine-grain micritic matrix, which may be surrounded by medium-grain cementing micrite. Different degrees of consolidation occur—some crumble easily, whereas others require some manual force to break. These pro-thrombolites consist of platforms >20 cm thick and/or fragments of assorted sizes and forms. In some cases the structures have lithified, forming rocky plates (thrombolites). The extension and wide distribution of pro-thrombolites around the La Paz lagoon suggests that these structures could have determined its evolution from an original (primitive) cove into a lagoon. That is, the formation of prothrombolites through the entrapment and binding of sediments may have eventually altered water circulation, promoting sand sedimentation causing the formation of the El Mogote sand bar. Likewise, pro-thrombolites may have formed large extensions of headlands through accretion. Thus, several square kilometers of populated land around the La Paz lagoon may have thrombolithic origin.
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    A New Small-Bodied Species of Bavayia (Reptilia: Squamata: Diplodactylidae) from Southeastern New Caledonia.
    (Honolulu, University of Hawaii Press, 2008-04) Bauer, Aaron M. ; Jackman, Todd R. ; Sadlier, Ross A. ; Shea, Glenn ; Whitaker, Anthony H.
    A new species of diplodactylid genus Bavayia, B. goroensis, is described from the Plaine des Lacs region of the Province Sud, New Caledonia. The new gecko is the smallest member of the Bavayia cyclura clade (49 mm snout-vent length) and, based on a molecular phylogeny, is basal within this group. It differs from other members of this group in its much smaller size, more gracile body, and lower number of precloacal pores and subdigital lamellae. The new species is known from only two locations, one of which is adjacent to extensive nickel mining operations. Because of its limited distribution and the direct and indirect threats posed by the proximity of mining to one of the populations, the species is here regarded as ‘‘Endangered.’’
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    Relative Abundance and Distribution of Mariana Swiftlets (Aves: Apodidae) in the Northern Mariana Islands.
    (Honolulu, University of Hawaii Press, 2008-04) Cruz, Justine B. ; Kremer, Shelly R. ; Martin, Gayle ; Williams, Laura L. ; Camacho, Vicente A.
    The endangered Mariana Swiftlet, Aerodramus bartschi (Mearns, 1909), occurs in its native habitat on only three islands worldwide—Guam, Saipan, and Aguiguan. It is locally extinct on the islands of Rota and Tinian, and numbers have declined on Guam. On Saipan and Aguiguan, the bird remains common. We present previously unpublished data from reports lodged with the Commonwealth of the Northern Mariana Islands Division of Fish and Wildlife combined with an analysis of arrival count data from surveys conducted regularly on Saipan (1985–2005) and opportunistically on Aguiguan (1985– 2002). Direct counts of swiftlets arriving at nesting caves did not permit islandwide population estimates but provided an index useful for assessing relative abundance. On Aguiguan, swiftlets occurred in only a few of the available caves; the population was small, more densely concentrated than on the other islands, and relatively stable. On Saipan, swiftlet numbers declined for the first part of the monitoring period (1985–1992), then increased significantly (1998–2005), and now stand at their highest level (>5,000 birds) since 1985. Large betweenyear fluctuations, high variation in colony attendance patterns, and occasional abandonment and recolonization of some caves were evident during the 20-yr monitoring period. Of the potential constraints to the population, pesticide use, typhoons and supertyphoons, habitat alteration by feral animals, human disturbance in the nesting caves, and predation remain areas of concern. Conservation measures may have lessened some disturbance events and nest damage by cockroaches, while other measures, such as translocation, may improve the species’ chances of persistence.