El Niño-Southern Oscillation (ENSO) phenomena and forest fires in the southwestern United States

Fire statistics (area burned) and fire-scar chronologies from tree rings show reduced fire activity during El Niño-Southern Oscillation (ENSO) in forests of Arizona and New Mexico. This relationship probably stems from increased fuel moisture after a wet winter and spring, but also could involve climatic controls on lightning activity at the onset of the monsoon season.

A statistical model of climates in the southwestern United States

EXTRACT (SEE PDF FOR FULL ABSTRACT): We describe an empirical-statistical model of climates of the southwestern United States. Boundary conditions include sea surface temperatures, atmospheric transmissivity, and topography. Independent variables are derived from the boundary conditions along 1000-km paths of atmospheric circulation. ... Predictor equations are derived over a larger region than the application area to allow for the increased range of paleoclimate. This larger region is delimited by the autocorrelation properties of climatic data.

The economic importance of marine angler expenditures in the United States.

In 1998, the National Marine Fisheries Service (NMFS) began a series of marine angler expenditure surveys in the coastal regions of the United States (U.S.) to evaluate marine recreational fishing expenditures and the financial impacts of these expenditures in each region and the U.S. as a whole. In this report, we use the previously estimated expenditure estimates to assess the total financial impact of anglers’ saltwater expenditures. Estimates are provided for sales, income, employment, and tax impacts for each coastal state in the U.S. Aggregate estimates are also provided for the entire U.S., excluding Alaska, Hawaii, and Texas. Direct, indirect, and induced effects associated with resident and non-resident angler expenditures were estimated using a regional input-output modeling system called IMPLAN Pro. Nationwide, recreational saltwater fishing generated over $30.5 billion in sales in 2000, nearly $12.0 billion in income, and supported nearly 350,000 jobs. Approximately 89 cents of every dollar spent by saltwater anglers was estimated to remain within the U.S. economy. At the state level, many of the goods anglers purchased were imports, and, as such, as little as 44 cents of every dollar stayed in Rhode Island and as much as 80 cents of every dollar stayed in Georgia. In the Northeast, the highest impacts were generated in New Jersey, even though recreational fishing expenditures in Massachusetts and Maryland were considerably higher. In the Southeast, the highest impacts were generated in Florida, and on the Pacific Coast, the highest impacts were generated in California. Expenditures on boat maintenance/expenses generated more impacts than any other expenditure category in the U.S. Expenditures on rods and reels was the single most important expense category in terms of generating impacts in most of the Northeast states. Expenditures on boat expenses generated the highest in most Southeast states, and expenditures for boat accessories produced the highest impacts in most Pacific Coast states.(PDF file contains 184 pages.)

Quantitative composition and distribution of the macrobenthic invertebrate fauna of the Continental Shelf ecosystems of the Northeastern United States

From the mid-1950's to the mid-1960's a series of quantitative surveys of the macrobenthic invertebrate fauna were conducted in the offshore New England region (Maine to Long Island, New York). The surveys were designed to 1) obtain measures of macrobenthic standing crop expressed in terms of density and biomass; 2) determine the taxonomic composition of the fauna (ca. 567 species); 3) map the general features of macrobenthic distribution; and 4) evaluate the fauna's relationships to water depth, bottom type, temperature range, and sediment organic carbon content. A total of 1,076 samples, ranging from 3 to 3,974 m in depth, were obtained and analyzed. The aggregate macrobenthic fauna consists of 44 major taxonomic groups (phyla, classes, orders). A striking fact is that only five of those groups (belonging to four phyla) account for over 80% of both total biomass and number of individuals of the macrobenthos. The five dominant groups are Bivalvia, Annelida, Amphipoda, Echninoidea, and Holothuroidea. Other salient features pertaining to the macrobenthos of the region are the following: substantial differences in quantity exist among different geographic subareas within the region, but with a general trend that both density and biomass increase from northeast to southwest; both density and biomass decrease with increasing depth; the composition of the bottom sediments significantly influences both the kind and quantity of macrobenthic invertebrates, the largest quantities of both measures of abundance occurring in the coarser grained sediments and diminishing with decreasing particle size; areas with marked seasonal changes in water temperature support an abundant and diverse fauna, whereas a uniform temperature regime is associated with a sparse, less diverse fauna; and no detectable trends are evident in the quantitative composition of the macrobenthos in relation to sediment organic carbon content. (PDF file contains 246 pages.)

Maturation of Nineteen Species of Finfish off the Northeast Coast of the United States, 1985-1990

Observations on maturation stages of nineteen species of economically important finfish off the Northeast coast of the USA were analyzed to examine relationships between fish size or age, and maturity. Maturation schedules and median lengths (L50) and ages (A50) at maturation were derived by fitting the logistic model to the observed proportions. Analyses were generally restricted to observations from 1985 to 1990 obtained during stratified random bottom trawl surveys conducted in spring and autumn by the Northeast Fisheries Science Center and the Commonwealth of Massachusetts Division of Marine Fisheries in waters of the continental shelf from Nova Scotia to Cape Hatteras, North Carolina. Butterfish, Peprilus triacanthus, attained sexual maturity at the smallest median length (11.4 cm, males) and pollock, Pollachius virens, at the highest (41.8 em, males). Median length at maturity for gadiforms ranged from 22.2 to 41.8 em. Within the pleuronectiforms, median length at maturity ranged from 19.1 to 30.4 cm. Median lengths for the pelagic and miscellaneous demersal species were in the same ranges as the pleuronectiforms. Butterfish also attained sexual maturity at the youngest median age (0.9 yr, both sexes) whereas redfish, Sebastes fasciatus, were the latest to mature (5.5 yr, both sexes). For gadids, the median age at maturity ranged from 1.3 to 2.3 yr. Within the pleuronectiforms, median age at maturity ranged from 1.3 to 4.4 yr and, for pelagic species, from 0.9 to 3.0 yr. Median lengths and ages for many species are lower than those reported in earlier studies of the same general region of the Northwest Atlantic. (PDF file contains 72 pages.)

Marine Flora and Fauna of the Northeastern United States: Erect Bryozoa

Forty-nine species of erect Bryozoa from a broad range of Cyclostome, Ctenostome, and Cheilostome families are described and illustrated, and an artificial dichotomous key is provided for their identification. In general, the marine bryozoan faunas of the northeastern coasts of the United States are poorly known; species records are sparse and voucher collections few, and it is certain that many more species occur in this region than are presently known. The species described here occur in intertidal, coastal or offshore habitats; some are well known and have been recorded on numerous previous occasions, others have been only rarely reported, while a few are known to occur commonly in the north of the region but have yet to be recorded south of Cape Cod. Some of the species described have not been recorded at all on northeastern coasts of the United States, but are widely distributed in North Atlantic continental shelf habitats and perhaps occur in similar parts of the outer shelf of this region. This fauna is thus provisional, but is intended to stimulate further work on the Bryozoa. (PDF file contains 52 pages.)

National Marine Fisheries Service Habitat Conservation Efforts in the Southeastern United States for 1988

Dataq uantifying the area of habitat affected by Federal programs that regulate development in coastal zones of the southeastern United States are provided for 1988. The National Marine Fisheries Service (NMFS) made recommendations on 3,935 proposals requiring Federal permits or licenses to alter wetlands. A survey of 977 of these activities revealed that 359,876 acres of wetlands that support fishery resources under NMFS purview were proposed for some type of alteration or manipulation. Almost 95 percent of this acreage was for impounding andl/or manipulation of water levels in Louisiana marshes. The NMFS did not object to alteration of 173,284 acres and recommended the conservation of 186,592 acres. To offset habitat losses, 1,827 acres of mitigation were recommended by the NMFS or proposed by applicants and/or the Corps of Engineers (COE). From 1981 to 1988 the NMFS has provided in depth analyses on 8,385 projects proposing the alteration of at least 656,377 acres of wetlands. A follow-up survey on the disposition of 339 permits handled by the COE during 1988 revealed that the COE accepted NMFS recommendations on 68 percent. On a permit-by-permit basis, 13 percent of NMFS recommendations were partially accepted, 17 percent were completely rejected, and 2 percent were withdrawn. The permit requests tracked by the NMFS proposed the alteration of 2,674 acres of wetlands. The COE issued permits to alter 847 acres or 32 percent of the amount proposed.

Temporal trends (2000–2011) and influences on fishery-independent catch rates for loggerhead sea turtles (Caretta caretta) at an important coastal foraging region in the southeastern United States

Seasonal trawling was conducted randomly in coastal (depths of 4.6–17 m) waters from St. Augustine, Florida, (29.9°N) to Winyah Bay, South Carolina (33.1°N), during 2000–03, 2008–09, and 2011 to assess annual trends in the relative abundance of sea turtles. A total of 1262 loggerhead sea turtles (Caretta caretta) were captured in 23% (951) of 4207 sampling events. Capture rates (overall and among prevalent 5-cm size classes) were analyzed through the use of a generalized linear model with log link function for the 4097 events that had complete observations for all 25 model parameters. Final models explained 6.6% (70.1–75.0 cm minimum straight-line carapace length [SCLmin]) to 14.9% (75.1–80.0 cm SCLmin) of deviance in the data set. Sampling year, geographic subregion, and distance from shore were retained as significant terms in all final models, and these terms collectively accounted for 6.2% of overall model deviance (range: 4.5–11.7% of variance among 5-cm size classes). We retained 18 parameters only in a subset of final models: 4 as exclusively significant terms, 5 as a mixture of significant or nonsignificant terms, and 9 as exclusively nonsignificant terms. Four parameters also were dropped completely from all final models. The generalized linear model proved appropriate for monitoring trends for this data set that was laden with zero values for catches and was compiled for a globally protected species. Because we could not account for much model deviance, metrics other than those examined in our study may better explain catch variability and, once elucidated, their inclusion in the generalized linear model should improve model fits.

The distribution of larval fishes of the Charleston Gyre Region off the southeastern United States in winter shaped by mesoscale, cyclonic eddies

Serial, cyclonic, mesoscale eddies arise just north of the Charleston Bump, a topographical rise on the continental slope and Blake Plateau, and characterize the U.S. outer shelf and upper slope in the region of the Charleston Gyre. This region was transected during the winters of 2000, 2001, and 2002, and hydrographic data and larval fishes were collected. The hydrodynamics of the cyclonic eddies of the Charleston Gyre shape the distribution of larval fishes by mixing larvae from the outer continental shelf and the Gulf Stream and entraining them into the eddy circulation at the peripheral margins, the wrap-around filaments. Over all years and transects (those that intercepted eddies and those that did not), chlorophyll a concentrations, zooplankton displacement volumes, and larval fish concentrations were positively correlated. Chlorophyll a concentrations were highest in filaments that wrapped around eddies, and zooplankton displacement volumes were highest in the continental shelf–Gulf Stream–frontal mix. Overall, the concentration of all larval fishes declined from inshore to offshore with highest concentrations occurring over the outer shelf. Collections produced larvae from 91 fish families representing continental shelf and oceanic species. The larvae of shelf-spawned fishes—Atlantic Menhaden Brevoortia tyrannus, Round Herring Etrumeus teres, Spot Leiostomus xanthurus, and Atlantic Croaker Micropogonias undulatus—were most concentrated over the outer shelf and in the continental shelf–Gulf Stream–frontal mix. The larvae of ocean-spawned fishes—lanternfishes, bristlemouths, and lightfishes—were more evenly dispersed in low concentrations across the outer shelf and upper slope, the highest typically in the Gulf Stream and Sargasso Sea, except for lightfishes that were highest in the continental shelf–Gulf Stream–frontal mix. Detrended correspondence analysis rendered groups of larval fishes that corresponded with a gradient between the continental shelf and Gulf Stream and Sargasso Sea. Eddies propagate northeastward with a residence time on the outer shelf and upper slope of ∼1 month, the same duration as the larval period of most fishes. The pelagic habitat afforded by eddies and fronts of the Charleston Gyre region can be exploited as nursery areas for feeding and growth of larval fishes within the southeastern Atlantic continental shelf ecosystem of the U.S. Eddies, and the nursery habitat they provide, translocate larvae northeastward.

Pacific sea surface temperature associations with southwestern United States summer rainfall and atmospheric circulation

Pacific sea surface temperatures (SSTs) are examined for their associations with (1) summer rainfall, and (2) the latitude location of the mid-tropospheric subtropical high pressure ridge (STR) in the southwestern United States during 1945 to 1986. Extreme northward (southward) displacements of STR are associated with wet (dry) summers over Arizona and an enhanced (weakened) gradient of SST off the California and Baja coasts. These tend to follow winters marked by positive (negative) phases of the PNA, Pacific/North America, teleconnection pattern. Recent decadal variations of Arizona summer rainfall (1950s wet; 1970s dry) appear similarly related to southwestern United States synoptic circulation and eastern Pacific SSTs.

Anomalous atmospheric circulation and large winter floods in six subregions of the southwestern United States

EXTRACT (SEE PDF FOR FULL ABSTRACT): We examined atmospheric circulation conditions conducive to occurrence of winter floods that exceed the 10-year peak discharge on rivers in six hydroclimatic subregions in Arizona, southern Utah, Nevada, and California. ... This relationship between flooding and broad-scale atmospheric patterns in the modern record will aid in paleoclimatic interpretations of paleoflood records over the last few thousand years.

Validation of a semi-Lagrangian, canonical regression model of climates in the southwestern United States

EXTRACT (SEE PDF FOR FULL ABSTRACT): A local climate model (LCM) has been developed to simulate the modern and 18 ka climate of the southwestern United States. ... LCM solutions indicate summers were about 1°C cooler and winters 11°C cooler at 18 ka. Annual PREC increased 68% at 18 ka, with large increases in spring and fall PREC and diminished summer monsoonal PREC. ... Validation of simulations of 18 ka climate indicate general agreement with proxy estimates of climate for that time. However, the LCM estimates of summer temperatures are about 5 to 10°C higher than estimates from proxy reconstructions.

Tree-ring reconstructions of winter climate and circulation indices for the southwestern United States

A key to understanding the causes for climate variability lies in understanding how atmospheric circulation influences regional climate. The goal of this research is to investigate the long-term relationships between atmospheric circulation and winter climate in the southwestern United States. Patterns of atmospheric circulation are described by circulation indices, and winter climate is defined as number of days with precipitation and mean maximum temperature for the winter wet season, November through March. Records of both circulation indices and climate variables were reconstructed with tree-ring chronologies for the period 1702-1983. The years of the highest and lowest values of circulation indices and climate variables were compared in order to investigate possible spatial and temporal relationships between extremes in circulation and climate.

Fishery resources of the United States of America

The term “fishery resources” is used in this book with a broad application. It includes the populations of the fishes and other organisms useful to men, the environment that makes life possible for them, the industry that exploits and utilizes them, and our knowledge about them by which we can conserve their productivity. This book aims to survey the present status of all these aspects of those fishery resources that are used or are available for use by United States anglers and commercial fishermen. It is planned primarily for the Congress, at its request, with the idea of giving to busy people, in condensed fashion, a perspective on its subject. (pdf contains 142 pages)

Population assessment of two stocks of white grunt, Haemulon plumieri, from the southeastern coast of the United States

Changes in the age structure and population size of white grunt, Haemulon plumieri, from North Carolina through the Florida Keys were examined using records of landings and size frequencies of fish from commercial, re~reational, and headboat fisheries from 1986-1998. Data were stratified into two geographical areas: North Carolina and South Carolina; and southeast Florida. Population size in numbers at age was estimated for each year and geographical area by applying an uncalibrated separable virtual population analysis (SVPA) to the landings in numbers at age. A calibrated virtual population analysis, FADAPT, was also run for data from North Carolina and South Carolina. SVPA and FADAPT were used to estimate annual, age-specific fishing mortality (F) for four levels of natural mortality (M = 0.20, 0.25, 0.30, and 0.35). The best estimate of M for white grunt is 0.30. Landings of white grunt in the Carolinas for the three fisheries have generally decreased in recent years, but have held fairly steady for the species in southeast Florida. Age at entry and age at full recruitment were age-1 and age-4 for the Carolinas, and age-l and age-3 for southeast Florida. With M = 0.30, levels of fishing mortality (F) on the fully-recruited ages were 0.23 for the Carolinas and 0.33 for southeast Florida. Spawning potential ratio (SPR) at M = 0.30 was 57% for the Carolinas and 61% for southeast Florida, which indicates that the species, by definition, has not been over-exploited by fishing. The results of this assessment of the white grunt population off the Carolinas agree with the recent F/FMSY analysis of white grunt (Anonymous, 1999). (PDF contaons 72 pages)