Hector Guzman

Smithsonian Tropical Research Institute · Naos Marine Laboratories

Leatherback turtles Dermochelys coriacea are globally endangered. This study tracked 30 individuals from the North Atlantic population tagged on the Caribbean Panama rookery (San San Pond Sak protected area, Bocas del Toro) over a period of 3 yr. We used satellite telemetry to investigate the probability that turtles switched between migration and...

Climate change is shifting animal distributions. However, the extent to which future global habitats of threatened marine megafauna will overlap existing human threats remains unresolved. Here we use global climate models and habitat suitability estimated from long-term satellite-tracking data of the world’s largest fish, the whale shark, to show t...

The Galapagos Marine Reserve is vital for cetaceans, serving as both a stopover and residency site. However, blue whales, occasionally sighted here, exhibit poorly understood migratory behavior within the Galapagos and the broader Eastern Tropical Pacific. This study, the first to satellite tag blue whales in the Galapagos (16 tagged between 2021 a...

Introduction This work presents an unsupervised learning-based methodology to identify and count unique manatees using underwater vocalization recordings. Methods The proposed approach uses Scattering Wavelet Transform (SWT) to represent individual manatee vocalizations. A Manifold Learning approach, known as PacMAP, is employed for dimensionality...

Trichechus manatus is one of 3 recognized extant species of manatees of the mammalian Order Sirenia. Currently, it is known by various vernacular names, none of which are descriptive of its biology and known distribution. This lack of standardization has led to confusion and miscommunication, hindering conservation efforts for this species. We prop...

In May 2022, twelve prickly sharks, Echinorhinus cookei Pietschmann 1928, were sighted at 151–350 m depth in the Cordillera de Coiba seamounts, Pacific Panama. This discovery expands our knowledge of the distribution and habitat use of this rare deep‐sea species. It underscores the potential significance of the Cordillera de Coiba seamounts, an off...

Geographic variation in the vocal behavior of manatees has been reported but is largely unexplored. Vocalizations of wild West Indian manatees (Trichechus manatus) were recorded with hydrophones in Florida from Florida manatees (Trichechus manatus latirostris), and in Belize and Panama from Antillean manatees (Trichechus manatus manatus) to determi...

The worldwide decline of coral reefs has renewed interest in coral communities at the edge of environmental limits because they have the potential to serve as resilience hotspots and climate change refugia, and can provide insights into how coral reefs might function in future ocean conditions. These coral communities are often referred to as margi...

This document summarizes the current conservation status of the scalloped hammerhead shark (Sphyrna lewini) in the Eastern Tropical Pacific (ETP), including knowledge gaps and conservation priorities. We used a semi-systematic literature review to compile and classify a total of 166 documents (i.e., scientific articles and grey literature) regardin...

Coral species, which function to build the framework structure of reef ecosystems, vary across sheltered to exposed environmental gradients. For centuries, conditions in sheltered environments that impact lagoonal reefs have been altered by local anthropogenic disturbances, while conditions in exposed environments that impact forereefs have largely...

The Antillean Manatee (Trichechus manatus manatus), an herbivore mammal which inhabits coastal and wetlands areas from Mex- ico and Central America to northern Brazil, is considered a threatened species by the International Union for Conservation of Nature (IUCN). Herein, the usage YOLOv5, a Deep Learning based model, was suc- cessfully implemented...

For organisms living in seasonal environments, timing of breeding is key to ensuring reproductive success. Accordingly, temperate and polar seabird species follow seasonal pulses, matching their breeding events with peaks in ocean productivity. However, the seasonality of breeding has been much less explored in tropical seabirds. Here, we report se...

Warming events in the Pacific Ocean are becoming more frequent, intense, and on a larger temporal and spatial scale. This has caused critical habitats of marine species to lose their quality and marine organisms respond by modifying their critical feeding and reproduction behaviors, as well as their distribution. The Northeast Pacific humpback whal...

Context: Golfo Dulce is a wintering ground of the Southeast Pacific population of humpback whales. Habitat use and spatial preferences of whales during their reproductive season must be addressed in order to effectively conserve this species. Aims: This study aims to determine patterns of spatial segregation and habitat use depending on humpback wh...

Whale sharks (Rhincodon typus) are found circumglobally in tropical, subtropical, and warm temperate waters, and their known seasonal aggregations and migratory movements are influenced by factors such as ocean currents, thermobiological systems, and patterns of productivity. Several locations in the eastern tropical Pacific Ocean are known habitat...

Significance Global vessel traffic is increasing alongside world economic growth. The potential for rising lethal ship strikes on endangered species of marine megafauna, such as the plankton-feeding whale shark, remains poorly understood since areas of highest overlap are seldom determined across an entire species range. Here we show how satellite...

Chapter 12. Status and trends of coral reefs of the Caribbean region, pp. 1-25. In: Souter, D., Planes, S., Wicquart, J., Logan, M., Obura, D., & Staub, F. (Eds.) Status of Coral Reefs of the World: 2020. Global Coral Reef Monitoring Network, International Coral Reef Iniciative, Australian Institute of Marine Science, & Australian Governement.

The large gorgonian genus Leptogorgia Milne Edwards & Haime, 1857 is abundant and widely distributed along coastlines and around oceanic islands in the Eastern Tropical Pacific, where it comprises 31 species with a wide bathymetric distribution. Material of Leptogorgia dictynna sp. nov. was collected at mesophotic reefs bordering marine protected a...

The whale shark (Rhincodon typus) is an endangered and highly migratory species, of which solitary individuals or aggregations are observed in oceans worldwide and for which conservation efforts are hindered by a lack of comprehensive data on genetic population connectivity. Tissue samples were collected from wandering whale sharks in Pacific Panam...

106,107 ✉ replying to A. V. Harry & J. M. Braccini Nature https://doi.org/10.1038/s41586-021-03463-w (2021) Our global analysis 1 estimated the overlap and fishing exposure risk (FEI) using the space use of satellite-tracked sharks and longline fishing effort monitored by the automatic identification system (AIS). In the accompanying Comment, Harry...

This article is a response to Murua et al.'s Matters Arising article in Nature, "Shark mortality cannot be assessed by fishery overlap alone," which arose from arising from N. Queiroz et al. Nature https://doi.org/10.1038/s41586-019-1444-4 (2019).

We report a new mark-recapture-based population estimate for the humpback whale Breeding Stock G (BSG), defined by breeding grounds on the northwestern coast of South America and southwestern Central America and feeding grounds around the Antarctic Peninsula and southern Chile. Photographic fluke catalogs from 23 research groups working in both bre...

The shallow waters of the Tropical Eastern Pacific (TEP) harbor a species-rich octocoral fauna, with seven genera and 124 octocoral species described to date for the region. Of these lineages, Pacifigorgia , with 35 species, is by far the most speciose and abundant shallow-water octocoral occurring in the region. The speciation mechanisms resulting...

Whale watching has become an important economic activity for many coastal areas where whales aggregate at certain times of year. Las Perlas Archipelago in Panama is a breeding ground for humpback whales, where the numbers of both visitors and tour operators have increased in recent years with little compliance and enforcement of regulations. Nevert...

Eastern gray whales undertake annual migrations between summer feeding grounds in the Bering and Chukchi Seas and winter breeding and calving lagoons in the west coast of Baja California, Mexico. On February 12, 2017, three adult gray whales were sighted at San José del Cabo, Mexico, in which one individual, named “María,” was tagged using a satell...

Ecotourism focused on whales and dolphins has become a popular activity and an important source of revenue for many countries. Whale watching is vital to supporting conservation efforts and provides numerous benefits to local communities including educational opportunities and job creation. However, the sustainability of whale-based ecotourism depe...

The present research aimed to evaluate the antibacterial activity of volatile organic compounds (VOCs) produced by octocoral-associated bacteria Bacillus sp. BO53 and Pseudoalteromonas sp. GA327. The volatilome bioactivity of both bacteria species was evaluated against human pathogenic antibiotic-resistant bacteria, methicillin-resistant Staphyloco...

Con especial satisfacción, compartimos con la sociedad panameña y la comunidad científica mundial, los resultados de 10 años de investigación científica, con una muestra de investigaciones que han recibido apoyos económicos por parte de la Secretaría Nacional de Ciencia, Tecnología e Innovación (Senacyt) en distintas áreas del conocimiento. Este co...

Effective ocean management and the conservation of highly migratory species depend on resolving the overlap between animal movements and distributions, and fishing effort. However, this information is lacking at a global scale. Here we show, using a big-data approach that combines satellite-tracked movements of pelagic sharks and global fishing fle...

To reduce the whale-vessel strike risk in the Gulf of Panama, the International Maritime Organization (IMO) adopted a Traffic Separation Scheme (TSS) with corresponding inshore traffic zones and seasonal (Aug–Nov) speed limits of ≤10 kn (Speed Over Ground, SOG) commencing December 2014. Here, we assessed compliance rates to these new regulations. V...

The species of the genus Psammogorgia Verrill, 1868 from the shallow waters of the tropical eastern Pacific were mainly described from 1846 to 1870. Very few contributions were published subsequently. Recently, the genus was revisited with the addition of two new species. However, a comprehensive generic study is still missing for the eastern Pacif...

The Magellan Strait is a narrow passage connecting the Pacific and Atlantic oceans in South America. An average of 2023 ships per year transit this corridor with 80% representing the international fleet. The southwestern part of the Strait in Chile is an important summer feeding area for humpback whales. Considering the risk to whales of feeding am...

We evaluated the potential of using convolutional neural networks in classifying spectrograms of Antillean manatee (Trichechus manatus manatus) vocalizations. Spectrograms using binary, linear and logarithmic amplitude formats were considered. Two deep convolutional neural networks (DCNN) architectures were tested: linear (fixed filter size) and py...

The effects of herbivores and sediment deposition on the structure and composition of the macroalgal communities on coral reefs were tested together experimentally and, in the field, in one of the most disturbed reefs of the Caribbean, the leeward reefs of the Bocas del Toro region, Panama. In this area, the potential natural herbivores have been r...

Introduction: False killer whale (Pseudorca crassidens) is a tropical and subtropical social species that live in groups with individuals of mixed ages and sex classes. False killer whales have been documented since the late 1990s in Southwestern Costa Rica. Objective: To estimate the abundance of false killer whales in Osa Peninsula waters. Meth...

ABSTRACT. Introduction: False killer whales (Pseudorca crassidens) is a tropical and subtropical social species that live in groups with individuals of mixed ages and sex classes. False killer whales have been documented since the late 1990s in southwestern Costa Rica. Objective: To estimate abundance of false killer whales in Osa Peninsula waters....

Accidental oil discharges pose acute and chronic risks on coral communities, but knowledge on the ecological long-term implications is fragmentary. Here, we examine the potential short-, mid- and long-term effects of a major oil spill on subtidal reef communities over a 30-year period using a multicontrol before-after-control-impact (BACI) approach...

Gorgonian octocorals are considered a prolific source of secondary metabolites with a wide range of biological activities, including anti-inflammatory activity. In particular, the genus Briareum is known for producing a wealth of diterpenes with complex chemical structures. The chemical study of the methanolic extract of Briareum asbestinum collect...

Sea turtles migrate from breeding grounds to foraging areas through the territorial waters of several countries. Olive ridleys lack clear migratory routes, which makes it a challenge for conservation. This study aimed to evaluate if the migratory behavior of olive ridleys nesting on the Pacific Coast of Panama is correlated to environmental conditi...

In Panama, shark fisheries were initially developed in the 1980s and progressively increased in production in the 1990s mainly due to the high demand for shark fins and meat from the international Asian market. Since then, and despite the exploitation rate (average 3,514 t year –1 ) and endangered status of some species, shark fisheries have seldom...

Trace metal and metalloid levels were measured in eggs of the NW Atlantic leatherback turtle (Dermochelys coriacea) from nesting grounds in the Bocas del Toro province, Panama, to infer exposure and associated risks to local communities. Samples were analyzed for a set of 26 essential and non-essential elements using inductively coupled plasma tech...

This work presents a methodology to automatically detect and identify manatee vocalizations in continuous passive acoustic underwater recordings. Given that vocalizations of each manatee present a slightly different frequency content, it is possible to identify individuals using a non-invasive acoustic approach. The recordings are processed in four...

Effective ocean management and the conservation of highly migratory species depend on resolving the overlap between animal movements and distributions, and fishing effort. However, this information is lacking at a global scale. Here we show, using a big-data approach that combines satellite-tracked movements of pelagic sharks and global fishing fle...

Although evidence suggests that humans have elevated global extinction rates and lowered global species richness, species richness at scales smaller than the globe can increase, decrease or remain the same. However, the role of spatial scale is rarely considered as a modifier in driving how richness change unfolds. We first observed richness change...

The octocoral fauna occurring at mesophotic depths (from 40 to 150 m) has been relatively unexplored. Recent expeditions to Hannibal Bank, a guyot seamount off Pacific Panama have yielded new octocoral species and new records for the tropical eastern Pacific. Herein, we describe a new species for the genus Psammogorgia , Psammogorgia pax sp. nov.,...

Abstract Whale sharks (Rinchodon typus) are found in shallow coastal and deep waters of tropical and warm temperate seas. Population genetic studies indicate high connectivity among populations, and an Indo-Pacific meta-population has been suggested with potential migrations among some ocean basins. Here, we present the satellite track of a trans-P...

The role and impact of killer whales Orcinus orca as predators of baleen whales has been emphasized by studies of humpback whales Megaptera novaeangliae. In this study, rake marks on the fluke were used as a proxy for predatory attacks in a sample of 2909 adult humpback whales and 133 calves from 5 breeding and 2 feeding locations in the eastern So...

Octocoral species are the main foundation species in rocky-wall coral communities off Pacific Panama; however, little is known about their reproductive biology. The present study quantifies the annual variation of reproductive traits in three common octocoral species from the tropical eastern Pacific Ocean with different colony morphology: the sea...

In the eastern Pacific Ocean, the genus Thesea has only been reported off Isla del Coco, Costa Rica, and La Jolla, California. Herein we describe a new species of Thesea from the threatened mesophotic zone of Hannibal Bank seamount and report the occurrence of the genus in Panama. The morphological characters of the species were analyzed and illust...

Chemical examination of the octocoral-associated Bacillus species (sp.) DT001 led to the isolation of pumilacidins A (1) and C (2). We investigated the effect of these compounds on the viability of Plasmodium falciparum and the mechanism of pumilacidin-induced death. The use of inhibitors of protein kinase C (PKC) and phosphoinositide 3-kinase (PI3...

Pseudoalteromonas is a genus of marine bacteria often found in association with other organisms. Although several studies have examined Pseudoalteromonas diversity and their antimicrobial activity, its diversity in tropical environments is largely unexplored. We investigated the diversity of Pseudoalteromonas in marine environments of Panama using...

The Winter aggregation of humpback whales off the southern coasts of Baja California peninsula constitute both a destination and transit area for these whales during their migratory cycle (Urbán et al., 2000). There are whales in transit from the mainland coasts and from the Revillagigedo Archipelago This is the aggregation with a higher turnover r...

Both natural and anthropogenic factors are changing coral-reef structure and function worldwide. Long-term monitoring has revealed declines in the local composition and species diversity of reefs. Here we report changes in coral-reef community structure over 12 yr (2000–2012) at 17 sites and three spatial scales (reef, gulf and country) in the Trop...

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The genus Adelogorgia is distinguished from other holaxonians in having conspicuously ornamented double-disc sclerites and leaf clubs in the coenenchyme, and non-mineralised axis cores. The two eastern Pacific species currently recognised as Adelogorgia are diagnosed and illustrated. Three new species for the genus are described from new localities...

Coastal ecosystems and the livelihoods they support are threatened by stressors acting at global and local scales. Here we used the data produced by the Caribbean Coastal Marine Productivity program (CARICOMP), the longest, largest monitoring program in the wider Caribbean, to evidence local-scale (decreases in water quality) and global-scale (incr...

Mixed effect models results. Word file including non-linear mixed effect model fits for temperature and visibility. (DOCX)

Site metadata. Word file including metadata for all CARICOMP stations included in the database and mixed effect model fits for temperature and visibility. (DOCX)

CARICOMP environmental database. Text file including all CARICOMP’s weekly environmental data. (TXT)

The Antillean manatee (Trichechus manatus manatus) is found in tropical and subtropical riverine and coastal waters across the Caribbean region. Little is known of its population status, particularly in Central America. We counted and mapped manatees using side-scan sonar in the San San Pond Sak wetland, a protected estuary in western Panama, for 1...