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At least 847 records · Page 47Linked to original sources
USGS2018

Advancing marine biological observations and data requirements of the complementary Essential Ocean Variables (EOVs) and Essential Biodiversity Variables (EBVs) Frameworks

Measurements of the status and trends of key indicators for the ocean and marine life are required to inform policy and management in the context of growing human uses of marine resources, coastal development, and climate change. Two synergistic efforts identify specific priority variables for monitoring: Essential Ocean Variables (EOVs) through the Global Ocean Observing System (GOOS), and Essential Biodiversity Variables (EBVs) from the Group on Earth Observations Biodiversity Observation Network (GEO BON). Both systems support reporting against internationally agreed conventions and treaties. GOOS, established under the auspices of the Intergovernmental Oceanographic Commission (IOC), plays a leading role in coordinating global monitoring of the ocean and in the definition of EOVs. GEO BON is a global biodiversity observation network that coordinates observations to enhance management of the world’s biodiversity and promote both the awareness and accounting of ecosystem services. Convergence and agreement between these two efforts are required to streamline existing and new marine observation programs to advance scientific knowledge effectively and to support the sustainable use and management of ocean spaces and resources. In this context, the Marine Biodiversity Observation Network (MBON), a thematic component of GEO BON, is collaborating with GOOS, the Ocean Biogeographic Information System (OBIS), and the Integrated Marine Biosphere Research (IMBeR) project to ensure that EBVs and EOVs are complementary, representing alternative uses of a common set of scientific measurements. This work is informed by the Joint Technical Commission for Oceanography and Marine Meteorology (JCOMM), an intergovernmental body of technical experts that helps international coordination on best practices for observing, data management and services, combined with capacity development expertise. Characterizing biodiversity and understanding its drivers will require incorporation of observations from traditional and molecular taxonomy, animal tagging and tracking efforts, ocean biogeochemistry, and ocean observatory initiatives including deep ocean and seafloor. The partnership between large-scale ocean observing and product distribution initiatives (MBON, OBIS, JCOMM, and GOOS) is an expedited, effective way to support international policy-level assessments (e.g., the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services or IPBES), along with the implementation of international development goals (e.g., the United Nations Sustainable Development Goals).

Frontiers in Marine Science↗
USGS2025

Biologging to identify nesting and non-nesting emergences for four species of imperiled sea turtles

Quantifying sea turtle nesting behavior is essential for recovery planning and evaluating management actions. Traditional monitoring approaches, based on nest counts from beach surveys, can misclassify non-nesting emergences, obscure true fecundity, and underestimate clutch frequency, metrics that directly influence population models and regulatory decisions. Here, we demonstrate that high-resolution acceleration data loggers (ADLs) can reliably discriminate nesting from non-nesting emergences across four imperiled species of sea turtles at sites in the Gulf of America, southeast USA, and Caribbean. From 60 recovered ADL deployments on green ( Chelonia mydas ; N = 10), hawksbill ( Eretmochelys imbricata ; N = 7), Kemp’s ridley ( Lepidochelys kempii ; N = 21), and loggerhead sea turtles ( Caretta caretta ; N = 22) lasting on average 17.5 ± 8.7 days (range 2–43 days), we identified 54 nesting events and 76 non-nesting emergences, with >97% accuracy when compared to direct observations. These data provide the first observer-validated, species-specific behavioral signatures of nesting phases and reveal correlations between egg-laying duration and clutch size. All non-nesting emergences occurred within 72 hours of subsequent nesting, allowing managers to anticipate nest deposition windows. By refining inter-nesting intervals and fecundity estimates, ADLs offer a practical path to reduce error in clutch frequency estimates. The integration of ADL-derived algorithms with satellite-transmitting tags would enable the remote, real-time monitoring of nesting activity, creating a system for the remote monitoring of inter-nesting intervals and nest fecundity that are crucial to quantify the impacts of climate change and other threats to sea turtle nesting habitat.

Alabama, Florida, North Carolina, Texas↗
USGS2008

The biological soil crusts of the San Nicolas Island: Enigmatic algae from a geographically isolated ecosystem

Composite soil samples from 7 sites on San Nicolas Island were evaluated quantitatively and qualitatively for the presence of cyanobacteria and eukaryotic microalgae. Combined data demonstrated a rich algal flora with 19 cyanobacterial and 19 eukaryotic microalgal genera being identified, for a total of 56 species. Nine new species were identified and described among the cyanobacteria and the eukaryotic microalgae that were isolated: Leibleinia edaphica, Aphanothece maritima, Chroococcidiopsis edaphica, Cyanosarcina atroveneta, Hassallia californica, Hassallia pseudoramosissima, Microchaete terrestre, Palmellopsis californiens, and Pseudotetracystis compactis. Distinct distributional patterns of algal taxa existed among sites on the island and among soil algal floras of western North America. Some algal taxa appeared to be widely distributed across many desert regions, including Microcoleus vaginatus, Nostoc punctiforme, Nostoc paludosum, and Tolypothrix distorta, Chlorella vulgaris, Diplosphaera cf. chodatii, Myrmecia astigmatica, Myrmecia biatorellae, Hantzschia amphioxys, and Luticola mutica. Some taxa share a distinctly southern distribution with soil algae from southern Arizona, southern California, and Baja California (e.g., Scenedesmus deserticola and Eustigmatos magnus). The data presented herein support the view that the cyanobacterial and microalgal floras of soil crusts possess significant biodiversity, much of it previously undescribed.

Western North American Naturalist↗
USGS2023

Burmese pythons in Florida: A synthesis of biology, impacts, and management tools

Burmese pythons ( Python molurus bivittatus ) are native to southeastern Asia, however, there is an established invasive population inhabiting much of southern Florida throughout the Greater Everglades Ecosystem. Pythons have severely impacted native species and ecosystems in Florida and represent one of the most intractable invasive-species management issues across the globe. The difficulty stems from a unique combination of inaccessible habitat and the cryptic and resilient nature of pythons that thrive in the subtropical environment of southern Florida, rendering them extremely challenging to detect. Here we provide a comprehensive review and synthesis of the science relevant to managing invasive Burmese pythons. We describe existing control tools and review challenges to productive research, identifying key knowledge gaps that would improve future research and decision making for python control.

Florida↗
USGS2021

A protocol for modelling generalised biological responses using latent variables in structural equation models

In this paper we consider the problem of how to quantitatively characterize the degree to which a study object exhibits a generalized response. By generalized response, we mean a multivariate response where numerous individual properties change in concerted fashion due to some internal integration. In latent variable structural equation modeling (LVSEM), we would typically approach this situation using a latent variable to represent a general property of interest (e.g., performance) and multiple observed indicator variables that reflect the specific features associated with that general property. While ecologists have used LVSEM in a number of cases, there is substantial potential for its wider application. One obstacle is that LV models can be complex and easily over-specified, degrading their value as a means of generalization. It can also be challenging to diagnose causes of misspecification and understand which model modifications are sensible. In this paper we present a protocol, consisting of a series of questions, designed to guide the researchers through the evaluation process. These questions address (1) theoretical development, (2) data requirements, (3) whether responses to perturbation are general, (4) unique reactions by individual measures, and (5) how far generality can be extended. For this illustration, we reference a recent study considering the potential consequences of maintaining biodiversity as part of agricultural management on the overall quality of grapes used for wine making. We extend our presentation to include the complexities that occur when there are multiple species with unique reactions.

One Ecosystem↗
USGS2001

Searching for biological specimens from midwestern parks: Pitfalls and solutions

This paper describes the results of searches of herbarium and museum collections and databases for records of vertebrate and vascular plant specimens that had been collected in 15 midwestern National Park System units. The records of these specimens were previously unknown to the National Park Service (NPS). In the course of our searches, numerous obstacles were encountered that prevented us from fully completing our task. These ranged from difficulties with the way databases are structured, to poor record-keeping, to incomplete or incorrect information on the actual location of specimens within collections. Despite these problems, we are convinced that the information to be gained from such searches in invaluable, and we believe that our experience, and the recommendations we offer, may well prove instructive to others undertaking this kind of work.

Arkansas, Indiana, Iowa, Kansas, Minnesota, Missou↗
USGS1971

Biology of larval sea lampreys (Petromyzon marinus) of the 1960 year class, isolated in the Big Garlic River, Michigan, 1960-65

The early life history of the sea lamprey, from hatching to the first capture of metamorphosed individuals, is described from observations on a known-age population isolated in a tributary of southern Lake Superior. The population had its origin in the spring of 1960, when 722 sea lampreys nearing spawning condition were introduced into the Big Garlic River, Marquette County, Michigan, a stream that had previously been free of lampreys because physical barriers prevented their upstream migration. The adults constructed 206 nests and spawned in 161 of them; an estimated 774,000 larvae were hatched. The average total lengths of larvae collected in October (when yearly growth was nearly complete) in 1960-65 were 13, 39, 63, 80, 92, and 107 mm in the successive years. A specially designed inclined-plane trap, installed at the lower end of the study area to monitor the downstream movement of larval and newly metamorphosed lampreys, captured 7,562 larvae in 1962-65 (none in 1960-61). The annual catch increased sharply from 9 in 1962 to 370 in 1963, 2,847 in 1964, and 4,336 in 1965. About 90% of each annual catch was taken by June 30. Most movement was at night. A total of 5,642 larvae were marked in 1962-65 by the subcutaneous injection of an insoluble dye, to study movement and distribution; 222 were recovered as larvae through 1965 (17 in the trap and 205 with an electric shocker). The recoveries of marked lampreys, the increase in density of larvae in the farthest downstream section of the study area, and the annual catches in the trap demonstrated that a large part of the population gradually shifted downstream. On the other hand, many larvae were still within less than 1 km from the place of hatching, after more than 5 years. The capture of four recently metamorphosed sea lampreys (two males and two females), 152-172 mm long, in the fall of 1965, established the minimum age at transformation for larvae in the Big Garlic River at 5 years. Age and length (with the exception of a possible minimum length) were determined not to be critical factors in metamorphosis. The presence of larvae 65-176 mm long (mean, 107 mm) in the river in 1965 indicated that metamorphosis of lampreys in a single year class takes place over a period of years.

Technical Report↗
USGS1978

Biology of larval and metamorphosing sea lampreys, Petromyzon marinus, of the 1960 year class in the Big Garlic River, Michigan, Part II, 1966-72

The 1960 year class of sea lampreys, Petromyzon marinus , isolated in a tributary of southern Lake Superior continued to yield information on the early life history of the sea lamprey. The larval population persisted and newly metamorphosed individuals were captured from 1966 until the study was terminated in 1972. The average lengths of larvae collected in October (when yearly growth is nearly complete) in successive years from 1966 to 1972 were 111, 113, 112, 114, 121, 128, and 129 mm. The average lengths of transforming lampreys during the same years were 150, 151, 145, 143, 144, 148, and 156 mm. A gradual downstream shift of the population took place. Catches in an inclined-plane trap at the lower end of the study area increased to a peak of 13,244 in the 1968-69 migration year (September 1-August 31), and then steadily decreased. As the number of lampreys decreased in the upper sections and increased in the lower ones, the changes in density were reflected in changes in growth rates. Although the mean length of ammocetes throughout the stream was 111 mm in 1966, it had increased by 1971 to 151 and 143 mm in the upstream sections (IV and V), but to only 115 mm in the densely populated area immediately above the trap. Of a total of 9,889 larvae marked in 1962-68 to study movement and distribution, 2,045 were recovered as larvae and 1,396 as newly transformed adults. Major downstream movements of larvae occurred during high water in April and May, and of transformed lampreys in mid-October through November. Each year about 40% (range, 30-68) of the annual production of transformed lampreys migrated from the Big Garlic River system in one 12-hour period, and 82% by the end of October. The Big Garlic River study proved conclusively that metamorphosis of a single year class occurs over a considerable number of years. Newly metamorphosed individuals were captured in almost steadily increasing numbers from 1965 (age V) to the termination of the study in 1972 (age XII). Many large ammocetes were still present in the study area in 1972, and it can safely be assumed that they would have continued to metamorphose for several more years.

Technical Report↗