Alexander M. Kerr

University of Guam | UOG · Marine Laboratory

Coral reefs, the most diverse of marine ecosystems, currently experience unprecedented levels of degradation. Diseases are now recognized as a major cause of mortality in reef-forming corals and are complicit in phase shifts of reef ecosystems to algal-dominated states worldwide. Even so, factors contributing to disease occurrence, spread, and impa...

Sexuality and reproductive mode are two fundamental life-history traits that exhibit largely unexplained macroevolutionary patterns among the major groups of multicellular organisms. For example, the cnidarian class Anthozoa (corals and anemones) is mainly comprised of gonochoric (separate sex) brooders or spawners, while one order, Scleractinia (s...

Managing fisheries for ecosystem resilience is essential, but practical guidance is limited by food-web complexity. Processes, mechanisms, and thresholds associated with ecosystem overfishing were investigated by combining traditional concepts in fisheries biology with recent advances in food-web modeling. Diverse coral-reef food webs were simplifi...

Many orb‐weaving spiders build webs invested with curious flags, spirals, or zig‐zagging ribbons of bright silk termed "decorations" or "stabilimenta". Web decorating arose some 150 million years ago in nine araneoid lineages, which have diversified into hundreds of species referable to about two dozen genera, with few reversions to non‐decorating...

More than half of reef-building corals (Scleractinia) participate in a nutritional symbiosis, known as photosymbio-sis, with photosynthetic dinoflagellates that ranges from obligate to facultative dependence. Fitting hidden-rates models allowing among-lineage variation in the rate of trait evolution to supertree and molecular phylogenies of Sclerac...

Edwin H. Bryan, Jr.'s monograph The Plants of Guam (1936-1941; 1956-1960) was an important addition to the botany of Guam and the Mariana Islands. It was also unique in Micronesian botany in that it was serialized twice in the popular press, appearing as a total of 191 brief articles in two now discontinued periodicals lacking wide circulation. Thi...

This paper explores how indigenous plant names have been referenced in the botanical literature. There are two species of trees in the Mariana Islands known in the indigenous language Chamoru as katot, a word referencing their irritating hairs and bark, Dendrocnide latifolia (Gaudich.) Chew (Urticaceae) and Claoxylon marianum Muell.Arg. (Euphorbiac...

Many orb-web weaving spiders add highly visible zigzagging silk "decorations" to their webs that are thought to function in prey attraction or predator avoidance. Despite the long history of studies on the form, frequency, and function of these structures, little attention has been paid to their mode of construction. Here, we report for the first t...

Spiders in the genus Uloborus (Uloboridae) often include silken structures in their webs called stabilimenta or decorations whose function is still debated. Here, I report on the form, frequency, and construction of the decorations built by U. glomosus (Feather-legged Orbweaver) based on a field survey of 129 webs in southeastern North Carolina. Ab...

Spiders in the genus Cyrtophora Simon, 1864 often incorporate debris and egg sacs in their webs. Based on a survey of online digital imagery, I report here that at least three species in this genus also include silk decorations: C. cylindroides (Walckenaer 1841), C. ikomosanensis (Bösenberg & Strand 1906), and C. moluccensis (Doleschall 1857). Thes...

We report the first instance of ontogenetic variation in web-decorating behaviour among conspecific populations of a spider. Small juveniles of Argiope appensa frequently spin discoid decorations in the Philippines, but only rarely do so in the Mariana Islands of Micronesia. Because discoid decorations have a defensive function, we suggest that nat...

Spiders in the genus Argiope Audouin, 1826 often include silken structures in their webs called decorations. Here, I report on the form and frequency of the vertical or linear decorations built by A. protensa L. Koch, 1872 as based on a survey of online digital imagery. Of 124 webs in 262 images clearly showing the web, 38.7% were decorated, less t...

Accounts of spider predation on lizards is commonly observed (Valdez 2020. Global Ecol. Biogeogr. 29:1691–1703) yet capture and escape sequences are less often reported. Here, I describe observations of attempted predation by the large orb-weaving Moluccan Tent Spider (Cyrtophora moluccensis) on Hemidactylus frenatus.

The sequence contains all odd prime numbers p, since they have N=2 divisors whose mean xbar is an integer and the sum of their squared mean deviations SS is even; therefore, their variance Var(p)=SS/N is an integer.

We surveyed the terrestrial gastropods of Alupat Island, a small uninhabited islet located in Hagåtña Bay, Guam. In three days of examining vegetation, leaf litter, and soil, we found 13 species of molluscs representing ten genera and eight families, all previously known from the main islands of the Marianas. We did not find any members of the fami...

Guam, the southernmost and largest island of the Mariana Islands, Micronesia, includes around its coastline several dozen small islets. They are primarily of consolidated reef-facies limestone, but include volcanic dikes and unconsolidated sandy islets. The largest is the atoll-like and forested Cocos Island (0.33 km2) atop the southern barrier ree...

Four species from the theridiid subfamily Argyrodinae Simon, 1894, all in the genus Argyrodes Simon, 1864, are here recognised from the Mariana Islands, western Micronesia, two of which are undescribed: a small form also found in western Micronesia and a large species from the southern Marianas. Two other species widely distributed around the weste...

All Argiope spiders build conspicuous planar webs that often include "decorations" or "stabilimenta", central strips or discs of bright silk whose function remains unclear; it is thought to attract prey, distract predators, or warn flying birds of the web's location. Here, we examine long-term site variation in decoration frequency in the webs of A...

[This corrects the article DOI: 10.1371/journal.pone.0202939.].

Argiope spp. are colourful and conspicuous spiders native worldwide, including the tropical western Pacific, where diversity is highest. They build near-vertical, planar webs, often "decorating" them with central strips or discs of bright silk whose function has long been debated. Here, I compile an illustrated and annotated guide to the Argiope sp...

In 2013, the remote Tubbataha Reef UNESCO World Heritage Site, in the western Philippines, experienced two ship groundings within four months: the USS Guardian (USSG), a US military vessel, and the Min Ping Yu (MPY), an illegal Chinese fishing vessel. Here, we present the results of coral disease assessments completed two years post-grounding and r...

Examples of physical injuries to corals. A. Colony fragmentation, which subsequent reattachment (at red stars); B. Colony abrasion/shearing; C. Colony fracture. The original colony is identified by the yellow circle; red stars identify fragments of the colony that were fractured from the colony on impact with the ship hull. Photo credits: L.J. Raym...

Raymundo, Licuanan, Kerr. Recovery Plots.xlsx—Spreadsheet for live coral percent cover by plot and year. (XLSX)

Small and large rubble patches within the Min Ping Yu impact border zone. A. small rubble patch (ground zero of hull impact scar to the left and large rubble in the foreground); B. large rubble patch (ground zero of hull impact scar to the right). Photo credits: W. Licuanan. (JPG)

Raymundo, Licuanan, Kerr. Coral Disease.xlsx—Spreadsheet for records of coral disease by site, species, and size class. (XLSX)

Examples of diseases of corals in Tubbataha Reef Nature Preserve. A. White syndrome; B. Growth anomaly; C. Skeletal eroding band disease; D. Brown band disease; E. Ulcerative white spot disease; F. Black band disease. Photo credits: L. Raymundo. (JPG)

Background/Question/Methods: Healthy fisheries support industrial economies, maintain resilient food webs, and offer countless services to society. The diversity of benefits translates into many disparate objectives for modern fisheries management to reconcile. Coral-reefs are introduced as a model system where objectives for maximizing fishing yie...

Background/Question/Methods: In 2013, the remote Tubbataha Reefs UNESCO World Heritage Site, in the western Philippines, experienced two ship groundings within four months: the USS Guardian (USSG), a US military vessel, and the Min Ping Yu (MPY), an illegal Chinese fishing vessel. Monitoring recovery in these pristine coral atolls began in 2014, by...

As with most land-snail faunas of the tropical Pacific islands, the approximately 100 native species of snails known from the Mariana Archipelago of western Micronesia are poorly documented and under pervasive threat of extinction. About 25% still await formal description. Most have only been collected from the two southernmost islands, Guam and Ro...

Of the ~1500 species of scleractinian corals, roughly 800 species participate in photosymbiosis: a nutritional mutualism with photosynthetic dinoflagellates of the genus Symbiodinium (also known as zooxanthellae). These zooxanthellate corals are the main bio-constructors of coral reefs in shallow-water, tropical to sub-tropical seas. Roughly 700 az...

Of the ~1500 species of scleractinian corals, roughly 800 species participate in photosymbiosis: a nutritional mutualism with photosynthetic dinoflagellates of the genus Symbiodinium (also known as zooxanthellae). These zooxanthellate corals are the main bio-constructors of coral reefs in shallow-water, tropical to sub-tropical seas. Roughly 700 az...

Conservation has long focused on preserving or restoring pristine ecosystems. However, understanding and managing novel ecosystems has grown in importance as they outnumber pristine ecosystems worldwide. While non-native species may be neutral or detrimental in pristine ecosystems, it is possible that even notorious invaders could play beneficial o...

Supplementary tables and figures for “Contrasting ecological roles of non-native ungulates in a novel ecosystem.”

We performed the first survey of terrestrial gastropods on Dano′ (Cocos Island). Dano′ is a 0.33 km2 uninhabited atoll island located 2.5 km southwest of Guam, the largest island in the Mariana archipelago, western Micronesia. In 4 days of examining vegetation, soil, and leaf litter, we found 14 species of mollusks arrayed in 12 genera and 11 taxon...

Non-native species, especially mammals such as cats, ungulates, and rats, are normally viewed as harmful in remote, oceanic island systems. However, in the context of novel ecosystems, they can fill in some lost functional roles when native species go extinct. The invasive brown treesnake (Boiga irregularis) is responsible for the functional extinc...

In 2015, the Marianas' three extant native tree snail species (Partula gibba, P. radiolata and Samoana fragilis) were among the first invertebrates from the islands to be added to the US endangered species list. Threats to these species include habitat destruction and introduced predators. Since their listing, our surveys have more than doubled the...

As with most land-snail faunas of the tropical Indo-west Pacific islands, the approximately 100 native species of snails known from the Mariana Archipelago of western Micronesia are poorly known and under pervasive threat of extinction. About 25% still await formal description. Most have only been collected from the southernmost islands, Guam, Rota...

Multi-locus phylogenetic studies of echinoderms based on Sanger and RNA-seq technologies and the fossil record have provided evidence for the Asterozoa-Echinozoa hypothesis. This hypothesis posits a sister relationship between asterozoan classes (Asteroidea and Ophiuroidea) and a similar relationship between echinozoan classes (Echinoidea and Holot...

Sea cucumbers (Holothuroidea) are a morphologically diverse, ecologically important, and economically valued clade of echinoderms; however, the understanding of the overall systematics of the group remains controversial. Here, we present a phylogeny of extant Holothuroidea assessed with maximum parsimony, maximum likelihood, and Bayesian approaches...

Variation in local environmental conditions can have pronounced effects on the population structure and dynamics of marine organisms. Previous studies on crown-of-thorns starfish, Acanthaster planci, have primarily focused on effects of water quality and nutrient availability on larval growth and survival, while the role of maternal nutrition on re...

Based on museum specimens and zooarchaeological material recovered by us, we note the historic presence of a population of sinistrally coiling Partula gibba Férussac, 1821 on the island of Guam. A single extinct population of this species is also known on an island > 150 km to the north. Hence, given the absence of sinistral populations on interven...

Background: One of our goals for the echinoderm tree of life project ( http://echinotol.org ) is to identify orthologs suitable for phylogenetic analysis from next-generation transcriptome data. The current dataset is the largest assembled for echinoderm phylogeny and transcriptomics. We used RNA-Seq to profile adult tissues from 42 echinoderm spe...

Fig.S2.pdf: This is a comparison of trees that resulted from searching on alignments of amino acids, coding sequences, and raw nucleotide sequences.

Fig.S3.pdf: This is the most likely tree found using coding sequences, the alignment of which resulted from our initial alignment-and-culling procedure.

TIMP_sequences.nexus: This is a nexus file that contains the sequence data used in this study.

Tissue inhibitors of metalloproteinases (TIMPs) help regulate the extracellular matrix (ECM) in animals, mostly by inhibiting matrix metalloproteinases (MMPs). They are important activators of mutable collagenous tissue (MCT), which have been extensively studied in echinoderms, and the four TIMP copies in humans have been studied for their role in...

Since 1962, the University of Guam has housed the GUAM herbarium collection, which comprises important collections of terrestrial and marine plants from the tropical western Pacific. This herbarium contains 57,647 archived specimens, mostly from Micronesia, an expanse in the western Pacific the size of the continental United States and encompassing...

White syndrome (WS) is currently the most prevalent disease of scleractinian corals in the Indo-Pacific region, with an ability to exist in both epizootic and enzootic states. Here, we present results of an examination of WS lesion dynamics and show that potentially associated traits of host morphology (i.e., branching vs. massive), lesion size, an...

This report provides an annotated transcription of the systematic accounts of the four then-known species of Mariana Island tree snails in the family Partulidae (Partula gibba, P. radiolata, P. salifana, and Samoana fragilis) from Kondo's (1955) unpublished and difficult to obtain Ph.D. dissertation on the systematics of Partulidae. The monograph i...

In December 2002, July 2007 and December 2009, we surveyed the sea cucumber fauna of the western Caroline Island of Yap (Federated States of Micronesia). We collected 37 species of holothuroids, including 32 species of aspidochirotes and five species of apodans. We found all 13 of the previously reported species and 24 new records for the islands—1...

Rationale One of our goals for the echinoderm tree of life project is to identify alignable orthologs for phylogenetic analysis from next-generation transcriptome data for echinoderms. As we achieve that goal much data that is not in line with that goal is filtered. However the filtered data can be valuable for other purposes such as virus discover...

The island of Nauru in eastern Micronesia potentially possesses a diverse array of echinoderms. I performed a small survey to explore echinoderm diversity in Nauru's shallow-water marine environments. In five days of surveying between 28 July to 1 August 1998, I surveyed 12 sites around the island on reef flats and forereef slopes to 20 m depth and...

The islands of Chuuk in the Caroline Islands of central Micronesia possess a diverse array of echinoderms, including holothuroids (sea cucumbers). We were invited to perform a survey to assess the diversity of holothuroids in Chuuk's shallow-water marine environments. In six days of surveying between 30 June to 9 July 2013, we surveyed 11 sites aro...

Partula desolata sp. nov. is described from two partial and two complete shells recovered from Late Holocene subfossil cave deposits on the island of Rota, Mariana Islands, in western Micronesia. The species is most similar to its presumed sister, the sympatric and still extant P. gibba Férussac, 1821, but is distinct from this and all other partul...

Sea cucumbers of the genus Bohadschia (Holothuroidea: Echinodermata) are among the larger and more common echinoderms on tropical coral reefs. While the genus is easy to identify and has been recognized for some time, the number and status of species have varied substantially for over a century. The species problem in Bohadschia is the result of hi...

Holothuria (Semperothuria) roseomaculata n. sp. is described from the main islands of Yap, Federated States of Micronesia. The ossicles are similar to those of its sister species, the sympatric H. (S.) flavomaculata Semper, 1868, but the new species is easily recognised, both in the field and among preserved specimens, by its much larger, rose-colo...

The Micronesian island of Guam has been an important site for the study of littoral tropical holothurian taxonomy for almost 200 years. Despite substantial attention by both expeditions and resident taxonomists, new records are still regularly added to the fauna, demonstrating the challenge of documenting even such large and well-known animals in a...

In 1980, the renowned French taxonomist G. Cherbonnier introduced the new subgenus Stichothuria to accommodate a remarkable New Caledonian species, Holothuria coronopertusa, characterised by enlarged dorsal and terminal papillae and an ossicle assemblage that combines tables, buttons and C-shaped bodies. The type specimen measured ± 37 cm in a high...

Recruitment overfishing (the reduction of a spawning stock past a point at which the stock can no longer replenish itself) is a common problem which can lead to a rapid and irreversible fishery collapse. Averting this disaster requires maintaining a sufficient spawning population to buffer stochastic fluctuations in recruitment of heavily harvested...

Spawner-recruit models. Four potential spawner-recruit models characterizing the relationship between spawner biomass of Lethrinus harak in Achang Marine Preserve and subsequent recruitment to the site. When h = 0.8, there is virtually no relationship between spawning stock and subsequent recruitment except at very low levels of spawner biomass. At...

Benthic habitat classifications used for stratification of sampling effort. Six general categories were adapted from Burdick [26]. (DOCX)

Estimates of the intrinsic rate of population increase ( r ) for model results from the present study and from long-term empirical data from Russ and Alcala [36] and Russ et al. [37] . (DOCX)

Vegetated coastal ecosystems provide goods and services to billions of people. In the aftermath of a series of recent natural disasters, including the Indian Ocean Tsunami, Hurricane Katrina and Cyclone Nargis, coastal vegetation has been widely promoted for the purpose of reducing the impact of large storm surges and tsunami. In this paper, we rev...

The number of graphs with nonzero edge sets on an n X n square grid is 2^(2*n*(n-1))-1.

In addition to a brief account of the need to have unique and unambiguous scientific names for taxa, this paper, annotated with examples of sea cucumbers, explains the basics of zoological nomenclature. In doing so it aims to reduce the confusion that exists among various breeds of end-users of taxonomists who may not fully understand the seemingly...