scholarly journals Recent changes in the diet and survival of Atlantic puffin chicks in the face of climate change and commercial fishing in midcoast Maine, USA

FACETS ◽  
2017 ◽  
Vol 1 (1) ◽  
pp. 27-43 ◽  
Author(s):  
Stephen W. Kress ◽  
Paula Shannon ◽  
Christopher O’Neal
Keyword(s):  
Body Weight ◽  
Gulf Of Maine ◽  
Clupea Harengus ◽  
Sea Surface ◽  
Melanogrammus Aeglefinus ◽  
Commercial Fishing ◽  
Surface Warming ◽  
Recent Climate ◽  
The Impact ◽  
Atlantic Puffin

We examined the diet of Atlantic puffin ( Fratercula arctica) chicks at three midcoast Maine, USA, colonies during the years 2005–2014 and found that the puffins at each island have a distinct diet that has changed in recent years. White hake ( Urophycis tenuis) is by far the most frequently delivered prey at each island. Atlantic herring ( Clupea harengus) is the second most frequently delivered food, but has declined in recent years on two islands. In contrast, butterfish ( Poronotus triacanthus), haddock ( Melanogrammus aeglefinus), and redfish ( Sebastes spp.) have increased in the puffin diet on all islands. Chick condition declined significantly from 1993 to 2009. We demonstrate that puffin chicks with greater body weight experience a higher chance of postfledging survival as compared to chicks with lower body weight. The years 2012–2013 were a period of extreme sea surface warming, in which puffin hatching success and productivity sharply declined. This study provides new insight into changes in marine communities, examining changes in chick diet. We discuss our findings in relation to warming sea surface temperatures, recent climate-related decline in puffin productivity in the Gulf of Maine, and the impact of commercial fisheries on forage fish.

scholarly journals Atlantic puffin diet reflects haddock and redfish abundance in the Gulf of Maine

2020 ◽  
Vol 656 ◽  
pp. 75-87
Author(s):  
KM Depot ◽  
LC Scopel ◽  
SW Kress ◽  
P Shannon ◽  
AW Diamond ◽  
...  
Keyword(s):  
Fisheries Management ◽  
Large Scale ◽  
Gulf Of Maine ◽  
Strong Predictor ◽  
Principal Component ◽  
Melanogrammus Aeglefinus ◽  
Generalist Predator ◽  
Successful Implementation ◽  
Ecosystem Based Fisheries Management ◽  
Atlantic Puffin

Ecosystem-based fisheries management, which considers the interactions between fisheries, target species, and the physical and biological components of ecosystems, is necessary to ensure that directed fisheries avoid adverse impacts to ecosystems over the long term. The successful implementation of ecosystem-based fisheries management requires an understanding of predator-prey relationships and ways to operationalize such relationships to inform fisheries management. Here, we investigated if the diet of a generalist predator, Atlantic puffin Fratercula arctica, can be used as an indicator of the abundance of 2 commercially exploited prey species (haddock Melanogrammus aeglefinus and Acadian redfish Sebastes fasciatus) in the Gulf of Maine. Because haddock and redfish eaten by puffins are juveniles (age 0), there is potential to use their proportions and lengths in puffin diet to better understand the processes influencing haddock and redfish recruitment. By using principal component analysis to develop measures of diet across multiple puffin colonies, we show both spatial variation and large-scale patterns in the proportions and lengths of haddock and redfish in puffin diet. Spawning stock biomass was a strong predictor of haddock proportion in puffin diet and a moderate predictor of redfish proportion; however, proportions in puffin diet did not predict age-1 recruitment, suggesting that variation in recruitment is caused by processes that occur after the puffin breeding season and which affect the survival of older juveniles. Haddock length on one colony was a moderate predictor of age-1 recruitment. We conclude that puffin diet can be used as an indicator of haddock and redfish abundance.

In situ acoustic estimates of the swimbladder volume of Atlantic herring (Clupea harengus)

2004 ◽  
Vol 61 (3) ◽  
pp. 323-337 ◽  
Author(s):  
Redwood W. Nero ◽  
Charles H. Thompson ◽  
J. Michael Jech
Keyword(s):  
Gulf Of Maine ◽  
Clupea Harengus ◽  
Sea Surface ◽  
Atlantic Herring ◽  
Acoustic Measurements ◽  
Neutral Buoyancy ◽  
Fish Weight ◽  
Neutrally Buoyant ◽  
Boyle’S Law

Abstract Acoustic measurements at 1.5–5 kHz on fish in the Gulf of Maine showed a swimbladder-resonance peak near 2.5 kHz at 160–190-m depth. Midwater trawls confirmed that the fish were likely to be Atlantic herring (Clupea harengus) of 19–29 cm length. Calculation using a model of swimbladder resonance gives swimbladder volumes of 1.2% of fish weight at 160–190 m. Extrapolation of this volume of gas using Boyle's Law suggests that at the sea surface, these herring would need to inflate their swimbladders by up to five to six times the volume required for neutral buoyancy. If these fish were to maintain this volume of gas with surface “gulping”, they would need to submerge from the sea surface with a 30% excess buoyancy. In general, swimbladders of the Clupeidae may have greater volumes of gas than if the fish were neutrally buoyant at the sea surface and the interpretation of HF-echosounder surveys may be additionally complex when the volume of gas and swimbladder volume are difficult to predict. Mechanisms of how herring obtain additional swimbladder gas are discussed.

An Analysis of Errors in Catch Projections for Canadian Atlantic Fish Stocks

1987 ◽  
Vol 44 (5) ◽  
pp. 967-981 ◽  
Author(s):  
Denis Rivard ◽  
Malcolm G. Foy
Keyword(s):  
Retrospective Analysis ◽  
Atlantic Cod ◽  
Age Groups ◽  
Clupea Harengus ◽  
Melanogrammus Aeglefinus ◽  
Fish Stocks ◽  
Stock Size ◽  
Input Variables ◽  
The Impact ◽  
Made In

Two techniques were used to identify and evaluate the components of error inherent in the catch projection method used in the assessment of Canadian Atlantic fish stocks. Firstly, a retrospective analysis was used to evaluate, for the projections made in 1979 and 1981, the impact of the actual error made in input variables such as catch-at-age, mean weight-at-age, recruitment, and stock size. Secondly, the variance of projections was estimated from the variance of input variables. From the retrospective analysis, the principal causes of error in catch projections were identified as the estimation of stock size, as well as the estimation and forecast of fishing mortalities for the projection years. The difference between actual catch and assumed catch for the first year of a 2-yr projection did not appear to be a major source of bias for catch projections. The coefficients of variation of the catch projected at F0.1 were estimated as follows: 15–20% for the projections of Atlantic cod (Gadus morhua) catches; 25–50% for those of haddock (Melanogrammus aeglefinus); 28% for those of pollock (Pollachius virens); 16% for those of redfish (Sebastes sp.); and 35–42% for those of herring (Clupea harengus). The uncertainties associated with abundance estimates for prerecruited age-groups and estimates of stock size emerged as key factors in the projections. Also important was the effect of uncertainties associated with the forecast of reference fishing mortalities (partial recruitment coefficients × F0.1) for the projection period, e.g. uncertainties resulting from changes in fish catchability, in fleet behavior, and in fishing patterns.

scholarly journals Consumption impacts by marine mammals, fish, and seabirds on the Gulf of Maine–Georges Bank Atlantic herring (Clupea harengus) complex during the years 1977–2002

2006 ◽  
Vol 64 (1) ◽  
pp. 83-96 ◽  
Author(s):  
W. J. Overholtz ◽  
J. S. Link
Keyword(s):  
Marine Mammals ◽  
Diet Composition ◽  
Gulf Of Maine ◽  
Demersal Fish ◽  
Pelagic Fish ◽  
Clupea Harengus ◽  
Sensitivity Analyses ◽  
Atlantic Herring ◽  
Georges Bank ◽  
The Impact

Abstract Overholtz, W. J. and Link, J. S. 2007. Consumption impacts by marine mammals, fish, and seabirds on the Gulf of Maine–Georges Bank Atlantic herring (Clupea harengus) complex during the years 1977–2002. ICES Journal of Marine Science, 64: 83–96. A comprehensive study of the impact of predation during the years 1977–2002 on the Gulf of Maine–Georges Bank herring complex is presented. An uncertainty approach was used to model input variables such as predator stock size, daily ration, and diet composition. Statistical distributions were constructed on the basis of available data, producing informative and uninformative inputs for estimating herring consumption within an uncertainty framework. Consumption of herring by predators tracked herring abundance closely during the study period, as this important prey species recovered following an almost complete collapse during the late 1960s and 1970s. Annual consumption of Atlantic herring by four groups of predators, demersal fish, marine mammals, large pelagic fish, and seabirds, averaged just 58 000 t in the late 1970s, increased to 123 000 t between 1986 and 1989, 290 000 t between 1990 and 1994, and 310 000 t during the years 1998–2002. Demersal fish consumed the largest proportion of this total, followed by marine mammals, large pelagic fish, and seabirds. Sensitivity analyses suggest that future emphasis should be placed on collecting time-series of diet composition data for marine mammals, large pelagic fish, and seabirds, with additional monitoring focused on the abundance of seabirds and daily rations of all groups.

scholarly journals On the use of omnidirectional sonars and downwards-looking echosounders to assess pelagic fish distributions during and after midwater trawling

2012 ◽  
Vol 70 (1) ◽  
pp. 196-203 ◽  
Author(s):  
Jason D. Stockwell ◽  
Thomas C. Weber ◽  
Adam J. Baukus ◽  
J. Michael Jech
Keyword(s):  
Gulf Of Maine ◽  
Pelagic Fish ◽  
Clupea Harengus ◽  
Small Pelagic Fish ◽  
Potential Applications ◽  
Fish Aggregation ◽  
And Function ◽  
The Impact ◽  
Size Estimates ◽  
Fish Distributions

Abstract Stockwell, J. D., Weber, T. C., Baukus, A. J., and Jech, J. M. 2013. On the use of omnidirectional sonars and downwards-looking echosounders to assess pelagic fish distributions during and after midwater trawling. – ICES Journal of Marine Science, 70:196–203. Small pelagic fish can play an important role in the structure and function of ecosystems, and there is increasing interest in their non-market value. At the scale of fish aggregations, however, the impact of fishing has received relatively little attention, with most effort devoted to impacts of vessel and gear avoidance on stock size estimates. We used concurrent deployment of a downwards-looking echosounder (Simrad ES60 system) and an omnidirectional sonar (Simrad SP90 system) during commercial pairtrawling operations for Atlantic herring (Clupea harengus) in the Gulf of Maine to examine their potential for studying the impacts of fishing on herring aggregations. We compared a number of aggregation metrics to illustrate similarities and differences between the two systems, and then qualitatively examined their properties during and after pairtrawling events to illustrate potential applications. Our results suggest that using both downwards-looking and omnidirectional systems provides complementary information on fish aggregation metrics. Future applications of these systems in before–after–control-impact (BACI) designs may help inform management agencies when evaluating potential impacts of fishing at the time and space scales of pelagic fish aggregations.

scholarly journals Interannual Variability and Trends in Sea Surface Temperature, Lower and Middle Atmosphere Temperature at Different Latitudes for 1980–2019

Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 454
Author(s):  
Andrew R. Jakovlev ◽  
Sergei P. Smyshlyaev ◽  
Vener Y. Galin
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Lower Stratosphere ◽  
Middle Atmosphere ◽  
Southern Oscillation ◽  
Lower Troposphere ◽  
Reanalysis Data ◽  
Sea Surface ◽  
The Arctic ◽  
The Impact

The influence of sea-surface temperature (SST) on the lower troposphere and lower stratosphere temperature in the tropical, middle, and polar latitudes is studied for 1980–2019 based on the MERRA2, ERA5, and Met Office reanalysis data, and numerical modeling with a chemistry-climate model (CCM) of the lower and middle atmosphere. The variability of SST is analyzed according to Met Office and ERA5 data, while the variability of atmospheric temperature is investigated according to MERRA2 and ERA5 data. Analysis of sea surface temperature trends based on reanalysis data revealed that a significant positive SST trend of about 0.1 degrees per decade is observed over the globe. In the middle latitudes of the Northern Hemisphere, the trend (about 0.2 degrees per decade) is 2 times higher than the global average, and 5 times higher than in the Southern Hemisphere (about 0.04 degrees per decade). At polar latitudes, opposite SST trends are observed in the Arctic (positive) and Antarctic (negative). The impact of the El Niño Southern Oscillation phenomenon on the temperature of the lower and middle atmosphere in the middle and polar latitudes of the Northern and Southern Hemispheres is discussed. To assess the relative influence of SST, CO2, and other greenhouse gases’ variability on the temperature of the lower troposphere and lower stratosphere, numerical calculations with a CCM were performed for several scenarios of accounting for the SST and carbon dioxide variability. The results of numerical experiments with a CCM demonstrated that the influence of SST prevails in the troposphere, while for the stratosphere, an increase in the CO2 content plays the most important role.

scholarly journals Body Mass, Physical Activity and Eating Habits Changes during the First COVID-19 Pandemic Lockdown in Poland

2021 ◽  
Vol 18 (11) ◽  
pp. 5682
Author(s):  
Hubert Dobrowolski ◽  
Dariusz Włodarek
Keyword(s):  
Physical Activity ◽  
Body Weight ◽  
Body Mass ◽  
Social Life ◽  
Eating Habits ◽  
High Energy ◽  
High Energy Density ◽  
Average Weight ◽  
Study Participants ◽  
The Impact

The outbreak of the COVID-19 pandemic caused a number of changes in social life around the world. In response to the growing number of infections, some countries have introduced restrictions that may have resulted in the change of the lifestyle. The aim of our study was to investigate the impact of the lockdown on body weight, physical activity and some eating habits of the society. The survey involving 183 people was conducted using a proprietary questionnaire. The mean age of the study participants was 33 ± 11 and mean height 169 ± 8 cm. An average increase in body weight was observed in 49.18% by 0.63 ± 3.7 kg which was the result of a decrease in physical activity and an increase in food consumption. We also observed a decrease in PAL from 1.64 ± 0.15 to 1.58 ± 0.13 and changes in the amount of food and individual groups of products consumption, including alcohol. Among the study participants who did not lose body mass, there was an average weight gain of 2.25 ± 2.5 kg. In conclusion, an increase of weight was shown in about half of the respondents in the study group which was associated with a decrease in physical activity and an increase in the consumption of total food and high energy density products.

scholarly journals Measurement of the Sea Surface Height with Airborne GNSS Reflectometry and Delay Bias Calibration

2021 ◽  
Vol 13 (15) ◽  
pp. 3014
Author(s):  
Feng Wang ◽  
Dongkai Yang ◽  
Guodong Zhang ◽  
Jin Xing ◽  
Bo Zhang ◽  
...  
Keyword(s):  
Wind Speed ◽  
Arrival Time ◽  
Elevation Angle ◽  
Satellite System ◽  
Sea Surface Height ◽  
Antenna Pattern ◽  
Sea Surface ◽  
Observation Method ◽  
Global Navigation Satellite ◽  
The Impact

Sea surface height can be measured with the delay between reflected and direct global navigation satellite system (GNSS) signals. The arrival time of a feature point, such as the waveform peak, the peak of the derivative waveform, and the fraction of the peak waveform is not the true arrival time of the specular signal; there is a bias between them. This paper aims to analyze and calibrate the bias to improve the accuracy of sea surface height measured by using the reflected signals of GPS CA, Galileo E1b and BeiDou B1I. First, the influencing factors of the delay bias, including the elevation angle, receiver height, wind speed, pseudorandom noise (PRN) code of GPS CA, Galileo E1b and BeiDou B1I, and the down-looking antenna pattern are explored based on the Z-V model. The results show that (1) with increasing elevation angle, receiver height, and wind speed, the delay bias tends to decrease; (2) the impact of the PRN code is uncoupled from the elevation angle, receiver height, and wind speed, so the delay biases of Galileo E1b and BeiDou B1I can be derived from that of GPS CA by multiplication by the constants 0.32 and 0.54, respectively; and (3) the influence of the down-looking antenna pattern on the delay bias is lower than 1 m, which is less than that of other factors; hence, the effect of the down-looking antenna pattern is ignored in this paper. Second, an analytical model and a neural network are proposed based on the assumption that the influence of all factors on the delay bias are uncoupled and coupled, respectively, to calibrate the delay bias. The results of the simulation and experiment show that compared to the meter-level bias before the calibration, the calibrated bias decreases the decimeter level. Based on the fact that the specular points of several satellites are visible to the down-looking antenna, the multi-observation method is proposed to calibrate the bias for the case of unknown wind speed, and the same calibration results can be obtained when the proper combination of satellites is selected.

scholarly journals The Effect of Atmosphere–Ocean Coupling on the Structure and Intensity of Tropical Cyclone Bejisa in the Southwest Indian Ocean

Atmosphere ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 688
Author(s):  
Soline Bielli ◽  
Christelle Barthe ◽  
Olivier Bousquet ◽  
Pierre Tulet ◽  
Joris Pianezze
Keyword(s):  
Tropical Cyclone ◽  
Mixed Layer ◽  
Heat Fluxes ◽  
Sea Surface ◽  
Ocean Mixed Layer ◽  
Surface Cooling ◽  
Southwest Indian Ocean ◽  
Left Hand ◽  
Sea Surface Cooling ◽  
The Impact

A set of numerical simulations is relied upon to evaluate the impact of air-sea interactions on the behaviour of tropical cyclone (TC) Bejisa (2014), using various configurations of the coupled ocean-atmosphere numerical system Meso-NH-NEMO. Uncoupled (SST constant) as well as 1D (use of a 1D ocean mixed layer) and 3D (full 3D ocean) coupled experiments are conducted to evaluate the impact of the oceanic response and dynamic processes, with emphasis on the simulated structure and intensity of TC Bejisa. Although the three experiments are shown to properly capture the track of the tropical cyclone, the intensity and the spatial distribution of the sea surface cooling show strong differences from one coupled experiment to another. In the 1D experiment, sea surface cooling (∼1 ∘C) is reduced by a factor 2 with respect to observations and appears restricted to the depth of the ocean mixed layer. Cooling is maximized along the right-hand side of the TC track, in apparent disagreement with satellite-derived sea surface temperature observations. In the 3D experiment, surface cooling of up to 2.5 ∘C is simulated along the left hand side of the TC track, which shows more consistency with observations both in terms of intensity and spatial structure. In-depth cooling is also shown to extend to a much deeper depth, with a secondary maximum of nearly 1.5 ∘C simulated near 250 m. With respect to the uncoupled experiment, heat fluxes are reduced from about 20% in both 1D and 3D coupling configurations. The tropical cyclone intensity in terms of occurrence of 10-m TC wind is globally reduced in both cases by about 10%. 3D-coupling tends to asymmetrize winds aloft with little impact on intensity but rather a modification of the secondary circulation, resulting in a slight change in structure.

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