Peter Houk

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Verified

Peter verified their affiliation via an institutional email.

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• PhD
• Professor at University of Guam

Fishing and pollution are chronic stressors that can prolong recovery of coral reefs and contribute to ecosystem decline. While this premise is generally accepted, management interventions are complicated because the contributions from individual stressors are difficult to distinguish. The present study examined the extent to which fishing pressure...

Coral reef assemblages, trophic interactions, and food web stability were examined across a remote and densely populated atoll, in the Republic of the Marshall Islands (RMI). The biomass of sharks, large-bodied piscivores, and secondary invertebrate consumers was expectedly larger in the absence of major human populations. Less intuitively, we repo...

A dearth of scientific data surrounding Micronesia's coral-reef fisheries has limited their formal assessment and continues to hinder local and regional management efforts. We approach this problem by comparing catch-based datasets from market landings across Micronesia to evaluate fishery status in the Commonwealth of the Northern Mariana Islands...

We hypothesize that the North Pacific transition zone chlorophyll front (TZCF) can episodically deliver enhanced phytoplankton levels that are linked to the emergence of adult populations of the coral eating starfish Acanthaster planci. In some years, the seasonally migrating TZCF bathes the northwest Hawaiian Islands with chlorophyll-a rich waters...

A central problem for jurisdictional scientists and managers is to reconcile how multiple environmental regimes, encompassing continuous, intermittent and human disturbances, influence pertinent ecological management targets. The presence of heterogeneous environments throughout the volcanic Northern Mariana Islands (NMI), coupled with the availabi...

The growing use of data-poor fisheries models provides unprecedented access to compelling stock metrics and management scenarios for coral-reef fisheries. Yet, it remains unclear how well the assumptions surrounding data-poor models derived from extensive cold-water fisheries fit the life histories and ecology of tropical coral-reef fishes. The pre...

Small-scale artisanal reef fisheries in the Pacific islands are prevalent and essential for society and culture, yet they remain poorly understood compared to commercial fisheries. General catch-and-effort trends have been characterized, but few studies have coupled landings data with fisher interviews to determine how both catch and effort may be...

Thermal-stress events on coral reefs lead to coral bleaching, mortality, and changes in species composition. The coral reefs of Yap, in the Federated States of Micronesia, however, remained largely unaffected by major thermal-stress events until 2020, when temperatures were elevated for three months. Twenty-nine study sites were examined around Yap...

Scientists and managers rely on indicator taxa such as coral and macroalgal cover to evaluate the effects of human disturbance on coral reefs, often assuming a universally positive relationship between local human disturbance and macroalgae. Despite evidence that macroalgae respond to local stressors in diverse ways, there have been few efforts to...

Escalating climate impacts on coral reefs are increasingly expanding management goals beyond preserving biodiversity to also maintaining ecosystem functions. Morphological and ecological species traits can help assess changes within reef communities beyond taxonomic identities alone. However, our limited understanding of trait interactions between...

A ridge-to-reef framework was developed for 26 watersheds around Guam. Dissolved inorganic nitrogen (DIN) data were collected for one year at the base of streams while coral and fish surveys were conducted on adjacent reefs. Two independent analyses revealed a similar 0.10 mg/l DIN threshold beyond which negative impacts to water quality and coral...

Climate change is increasing disturbance events on coral reefs with poorly understood consequences for fish population dynamics and fisheries management. Given growing concerns over food security for the tropical Pacific, we assessed fisheries management policies across a suite of Micronesian islands since 2014 as climate disturbance events have in...

In coral reef systems, increasingly frequent, severe climate change-driven disturbances are responsible for declines in vulnerable species, and a reorganisation of assemblages. Whilst these changes will certainly elicit shifts in ecosystem functioning, how trait distributions and cross-taxon interactions are altered remains largely unmeasured, hamp...

Ocean warming is increasing the incidence, scale, and severity of global-scale coral bleaching and mortality, culminating in the third global coral bleaching event that occurred during record marine heatwaves of 2014-2017. While local effects of these events have been widely reported, the global implications remain unknown. Analysis of 15,066 reef...

Localized stressors compound the ongoing climate‐driven decline of coral reefs, requiring natural resource managers to work with rapidly shifting paradigms. Trait‐based adaptive management (TBAM) is a new framework to help address changing conditions by choosing and implementing management actions specific to species groups that share key traits, v...

Harvesting models are based upon the ideology that removing large, old individuals provides space for young, fast‐growing counterparts that can maximize (fisheries) yields while maintaining population stability and ecosystem function. Yet, this compensatory density dependent response has rarely been examined in multispecies systems. We combined ext...

Island communities that rely on reef fish are currently faced with declining marine resources due to unsustainable fishing and climate change. Identification of genetic stocks through phylogeographic analyses has become a growing field of study with conservation implications, but genetic information on reef fish in Micronesia is limited. In this st...

El Niño Southern Oscillation (ENSO) events modulate oceanographic processes that control temperature and productivity in tropical waters, yet potential interactions with low frequency climate variability, such as the Pacific Decadal Oscillation (PDO), are poorly understood. We show that ENSO and PDO together predicted (i) maximum sea-surface temper...

Many seagrass habitats are susceptible to undesirable macroalgal overgrowth in response to growing watershed development, but the mechanisms leading to overgrowth remain unresolved. Partitioning the influences of intermittent seasonal cycles and directional human stressors is one main challenge. We examined the dynamics of macroalgal canopies withi...

Marine protected areas (MPAs) have emerged as a valuable tool in biodiversity conservation and fisheries management. However, the effective use of MPAs depends upon the successful integration of social and eco- logical information. We investigated relationships between the social system structure of coastal communities alongside biological data des...

Marine protected areas (MPAs) have emerged as a valuable tool in biodiversity conservation and fisheries management. However, the effective use of MPAs depends upon the successful integration of social and ecological information. We investigated relationships between the social system structure of coastal communities alongside biological data descr...

Without drastic efforts to reduce carbon emissions and mitigate globalized stressors, tropical coral reefs are in jeopardy. Strategic conservation and management requires identification of the environmental and socioeconomic factors driving the persistence of scleractinian coral assemblages—the foundation species of coral reef ecosystems. Here, we...

Water quality and fisheries exploitation are localized, chronic stressors that impact coral reef condition and resilience. Yet, quantifying the relative contribution of individual stressors and evaluating the degree of human impact to any particular reef are difficult due to the inherent variation in biological assemblages that exists across and wi...

Trait diversity is believed to influence ecosystem dynamics through links between organismal traits and ecosystem processes. Theory predicts that key traits and high trait redundancy – large species richness and abundance supporting the same traits – can buffer communities against environmental disturbances. While experiments and data from simple e...

Spatial expansions can provide a false sense of sustainability to fish markets and their consumers who perceive stable landings through time despite localized depletions. This study examined attributes of monthly landings and changes in size structures within a commercial coral-reef fishery that had stable landings for 11 years. Regression models r...

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...

Aim Use a fishery‐independent metric to model and map regional‐scale fishing impact, and demonstrate how this metric assists with modelling current and potential fish biomass to support coral‐reef management. We also examine the relative importance of anthropogenic and natural factors on fishes at biogeographical scales. Location Reefs of five jur...

The consistent supply of fresh fish to commercial markets may mask growing fishing footprints and localized depletions, as fishing expands to deeper/further reefs, smaller fish, and more resilient species. To test this hypothesis, species-based records and fisher interviews were gathered over one year within a large, demand-driven coral-reef fisher...

Monthly fishing success. Mean monthly spearfishing landings (gray bars) and bottomfishing landings (black bars) with respect to the annual means (dashed lines). (EPS)

Fishing success and profit at different reef habitats. Mean catch (a) and net income (b) for bottomfishing (black bars) and spearfishing (gray bars) within different reef habitats. (EPS)

Fishing effort Vs landings. Number of fishing trips recorded and total landings from different barrier-reef sections (shapes) and seasons (colors). (EPS)

Table A. Mean and overall landings data from different weekdays. Table B. Catch and profit data for different reef types and gear. Table C. Frequency of trips and overall landings data for different reef sections and seasons. Table D. Mean landings data across different winspeeds and distance to full-moon. Table E. Mean fisher catch-per-trip data a...

Variable density dependence within multispecies fisheries results in species restructuring as exploitation intensifies that is poorly understood. We examined unique species-based records across 25 years of exploitation to evaluate patterns, consequences, and predictions of species replacements within three coral-reef fisheries. Body-size was an exp...

Fisheries represent a fundamental resource linking social and ecological systems. Yet, unsustainable fishing regimes prevail across many tropical regions as a result of growing consumer demand and market expansion. Using the extensive reef-fish trade between Chuuk and Guam (Micronesia) as a case study, we examined 12 years of commercial reef-fish e...

Study Highlights:  This study is the first in the U.S. Territory of American Samoa to cover wide temporal and spatial scales in assessing watershed health using an integrated water quality and biological condition scoring framework.  Results can be used to help guide development of water quality thresholds for Dissolved Inorganic Nitrogen (DIN)...

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...

Coral-reef fisheries pose a problem for traditional forms of management because stock assessments and demographic data are limited in diverse systems. We used catch records coupled with fisher interviews to derive hierarchical indicators of fishery status by (1) characterizing catch-and-effort trends with respect to environmental factors, (2) asses...

Understanding how and why coral reefs have changed over the last twenty to thirty years is crucial for sustaining coral-reef resilience. We used a historical baseline from Kosrae, a typical small island in Micronesia, to examine changes in fish and coral assemblages since 1986. We found that natural gradients in the spatial distribution of fish and...

Ecological resilience assessments are an important part of resilience-based management (RBM) and can help prioritize and target management actions. Use of such assessments has been limited due to a lack of clear guidance on the assessment process. This study builds on the latest scientific advances in RBM to provide that guidance from a resilience...

Adaptive management implies a continuous knowledge-based decision-making process in conservation. Yet, the coupling of scientific monitoring and management frameworks remains rare in practice because formal and informal communication pathways are lacking. We examined 4 cases in Micronesia where conservation practitioners are using new knowledge in...

The individual contribution of natural disturbances, localized stressors, and environmental regimes upon longer-term reef dynamics remains poorly resolved for many locales despite its significance for management. This study examined coral reefs in the Commonwealth of the Northern Mariana Islands across a 12-year period that included elevated Crown-...

The individual contribution of natural disturbances, localized stressors, and environmental regimes upon longer-term reef dynamics remains poorly resolved for many locales despite its significance for management. This study examined coral reefs in the Commonwealth of the Northern Mariana Islands across a 12-year period that included elevated Crown-...

A scarcity of life-history data currently exists for many exploited coral reef fishes, hindering our ability to interpret fishery dynamics and develop sound conservation policies. In particular, parrotfishes (Family Labridae) represent a ubiquitous and ecologically important group that is increasingly prevalent in commercial and artisanal fisheries...

Coral-reef fisheries play a central role in Pacific Island societies for their cultural, subsistence and economic values. Despite their importance, management of coral reef fisheries continues to be hampered by difficulties in estimating accurate fish landings. This study focuses upon both commercial and non-commercial reef-fish landings in the Com...

Watershed discharge, water quality, and seagrass assemblages were examined along the western coast of Yap Proper, Micronesia. Submarine groundwater discharge (SGD) during low tides associated with new and full moons contributed disproportionally to freshwater delivery where compromised Thalassia habitats existed. Despite SGD influence, nutrient sam...

Despite a steady growth in coral-reef monitoring efforts, the application of the monitoring results to decisionmaking often remains limited, because questions that can be answered are frequently posed after monitoring commences, rather than having the questions define the data to be gathered. We review how hierarchical, question-driven frameworks c...

Coral bleaching and mortality are predicted to increase as climate change-induced thermal-stress events become more frequent. Although many studies document coral bleaching and mortality patterns, few studies have examined deviations from the expected positive relationships among thermal stress, coral bleaching, and coral mortality. This study exam...

This study addresses the coupled themes of science and conservation by characterizing and evaluating the coral reefs around Yap, Federated States of Micronesia. Reef types, and the inherent environmental regimes they constitute, were found to be good predictors of distinct modern assemblages, with minimally overlapping species occurrences. Corals f...

In 2004-2005, several species of marine fish were collected for mercury (Hg) analysis from Saipan Lagoon, Saipan, Commonwealth of the Northern Mariana Islands. Relatively high concentrations were found in representatives from the Hafa Adai Beach area located some distance from known sources of Hg contamination. A follow-up investigation aimed at id...

Coral colony size-class distributions for four sites where coral assemblages were initially similar but varied in the years following cyclone Heta. At site 10 there was a significant change in colony size (P<0.05, Kolmogorov-Smirnov cumulative frequency test), while at site 11 there was a non-significant shift in colony size to larger, mainly Porit...

Environmental characteristics associated with each site, numbers in parentheses refer to site location (Fig. 1). Reef types are categorized as follows: 1) primary framework reefs with interstitial porosity, common to the south side of Tutuila, 2) primary framework reefs with a well-cemented basement, common to the north side, and 3) sand and patche...

Results from pairwise testing of benthic substrate ratios for four sites where coral assemblages were initially similar but varied in the years following cyclone Heta. Local site names and site numbers referring to Figure 1 are shown. P-values are as follows: (*P<0.05, **P<0.01, and ***P<0.001). (0.84 MB EPS)

Compared with a wealth of information regarding coral-reef recovery patterns following major disturbances, less insight exists to explain the cause(s) of spatial variation in the recovery process. This study quantifies the influence of herbivory and water quality upon coral reef assemblages through space and time in Tutuila, American Samoa, a Pacif...

This study identifies linkages between regional ocean productivity and the emergence of large Acanthaster planci starfish populations in Vanuatu. Positive correlations were found between wind stress, chlorophyll-a, and upwelling during January–February 2009, corresponding with coral-eating starfish occurrences. Further, temporal associations have e...

Despite a wealth of laboratory experiments describing seagrass growth and competitive interactions with macroalgae under varying nutrient concentrations, there is limited information available from field studies conducted in complex natural environments. We examined ecological change over time in the Saipan Lagoon, Western Pacific Ocean. Here, seag...

This study describes a step-by-step process used to design an effective benthic video survey component of the Commonwealth of the Northern Mariana Islands long-term monitoring program. Documenting abundance of major benthic groups at relatively large spatial scales, at the appropriate localities, can empower monitoring programs with the capacity to...

Reef development varies considerably around the high, raised-limestone islands of the Commonwealth of the Northern Mariana Islands (CNMI). Here we examine the modern assemblages at 30 sites for coral composition, colony density, colony size, and fidelity. We defined four reef types and hypothesize the presence of environmentally driven ecological s...

The objective of BASELINE is to publish short communications on different aspects of pollution of the marine environment. Only those papers which clearly identify the quality of the data will be considered for publication. Contributors to Baseline should refer to 'Baseline-The New Format and Content' (Mar. Pollut. Bull. 42, 703-704).

The Mariana Islands are a chain of 16 volcanic peaks stretching over a distance of approximately 2,500 km from 13° to 21° N latitude and centered at 145° E longitude (Fig. 19.1). Politically, the area is divided into two jurisdictions, Guam and the Commonwealth of the Northern Mariana Islands. Guam is a US territory located at 13°28' N, 144°45' E a...

These westernmost territories of the United States are where “America’s day begins”, and contain the most diverse coral reefs under the US flag (Randall 1995; Paulay 2003). The Mariana Islands have a long history of dedicated coral reef investigations by international and US researchers begun by Agassiz (1903). Despite having been discovered by the...

The Saipan Lagoon (Northern Mariana Islands) was first examined for benthic composition and habitat distribution in the late 1940s. Here, we employ a 4-stage approach to evaluate and explain change in the distribution of the 9 habitats previously demarcated. We show that there have been considerable reductions in seagrass, staghorn Acropora, and Ac...

American Samoa consists of five main volcanic islands and two atolls, which are situated in the central tropical South Pacific (Figure 10.1) at approximately 14°S and 170°W. American Samoa is the only U.S. territory located south of the equator. It experiences seasons opposite to those in all other U.S. areas, and has atmospheric and oceanic circul...

Thesis (Ph. D.)--Florida Institute of Technology, 2006. Includes bibliographical references (leaves 111-125).

Surveys were completed on Tutuila Island, American Samoa, to characterize reef development and assess the impacts of non-point source pollution on adjacent coral reefs at six sites. Multivariate analyses of benthic and coral community data found similar modern reef development at three locations; Aoa, Alofau, and Leone. These sites are situated in...

The 290 km long Mariana Islands Archipelago encompasses 14 islands of the U.S. Commonwealth of the Northern Mariana Islands (CNMI), the U.S. Territory of Guam, and numerous offshore banks (Figure 15.1). From a geological perspective, the islands can be divided into two groups: a southern and a northern island arc region. Although the islands of the...

This report, which is Chapter 14 in the Status of Coral Reefs of the World: 2004 report by Wilkinson (ed.)., addresses the status of coral reef ecosystems of Micronesia and American Samoa based on information presented in more detailed reports, such as "The State of Coral Reef Ecosystems of the United States and Pacific Freely Associated States: 2...

The coral reefs in this region are comparatively healthy, although there was extensive damage to the reefs in Palau during the coral bleaching event in 1998 and levels of human pressures are increasing, but not to the levels of reefs in nearby Asia. These countries and territories are affiliated with the USA and are currently included in many of th...