Changes in the movement and calling behavior of minke whales (Balaenoptera acutorostrata) in response to navy training

This research was funded by the U.S. Office of Naval Research under grant number N000141612859. The passive acoustic data were recorded under support by COMPACFLT for the Navy Marine Species Monitoring Program. The call association tracking algorithm was developed under a separate U.S. Office of Naval Research project (2011–2015 Advanced Detection, Classification and Localization, grant number: N0001414IP20037).Many marine mammals rely on sound for foraging, maintaining group cohesion, navigation, finding mates, and avoiding predators. These behaviors are potentially disrupted by anthropogenic noise. Behavioral responses to sonar have been observed in a number of baleen whale species but relatively little is known about the responses of minke whales (Balaenoptera acutorostrata). Previous analyses demonstrated a spatial redistribution of localizations derived from passive acoustic detections in response to sonar activity, but the lack of a mechanism for associating localizations prevented discriminating between movement and cessation of calling as possible explanations for this redistribution. Here we extend previous analyses by including an association mechanism, allowing us to differentiate between movement responses and calling responses, and to provide direct evidence of horizontal avoidance responses by individual minke whales to sonar during U.S. Navy training activities. We fitted hidden Markov models to 627 tracks that were reconstructed from 3 years of minke whale (B. acutorostrata) vocalizations recorded before, during, and after naval training events at the U.S. Navy's Pacific Missile Range Facility, Kauai, Hawaii. The fitted models were used to identify different movement behaviors and to investigate the effect of sonar activity on these behaviors. Movement was faster and more directed during sonar exposure than in baseline phases. The mean direction of movement differed during sonar exposure, and was consistent with movement away from sonar-producing ships. Animals were also more likely to cease calling during sonar. There was substantial individual variation in response. Our findings add large-sample support to previous demonstrations of horizontal avoidance responses by individual minke whales to sonar in controlled exposure experiments, and demonstrate the complex nature of behavioral responses to sonar activity: some, but not all, whales exhibited behavioral changes, which took the form of horizontal avoidance or ceasing to call.Publisher PDFPeer reviewe

North Pacific minke whales call rapidly when calling conspecifics are nearby

This research was supported by Commander, U.S. Pacific Fleet (Code N465JR, Award Number N0007020WR0EP8F) and tool development utilized for this analysis was supported by the U.S. Navy’s Living Marine Resources Program (Award Number N0002520WR0141R).North Pacific minke whale (Balaenoptera acutorostrata) boing calls are commonly detected in Hawaiian waters. When producing boing vocalizations, minke whales seem to be in one of two calling behavioral states. Most often minke whales produce boings with inter-call intervals of several minutes, but sometimes minke whales call rapidly with inter-call intervals of less than a minute. Since minke whales are difficult to detect visually, cue-rate-based density estimation using passive acoustic monitoring has been proposed. However, the variables that influence cue rate or calling rate are poorly understood in most whales, including minke whales. We collected passive acoustic recordings from 47 bottom-mounted hydrophones at the Pacific Missile Range Facility’s instrumented range off the coast of Kauaʻi, Hawaiʻi to test the hypothesis that minke whales call more rapidly when closer in proximity to other calling conspecifics. A total of 599 days of data were recorded between August 2012 and July 2017 and were automatically post-processed to detect, classify, and localize calls. Localized calls were grouped into tracks and manually validated, resulting in 509 individual tracks composed of 36,033 calls within a 16 x 39 km focal study area. Tracked minke whales exhibited a strong bimodal call rate with means of one call every 6.85 min (σ= 2.54 min) and 0.63 min (σ= 0.36 min). We ran hidden Markov models to quantify the relationship between call rate and the distance to the nearest calling conspecific. Overall, the probability of the higher call rate occurring increased as the distance to the nearest conspecific decreased, and the probability of the lower call rate occurring increased as the distance to the nearest conspecific increased. We also examined individual track data and found that minke whales may also exhibit other responses (i.e. increased speed, changes in heading, and cessation of calling) when calling conspecifics are nearby. These findings provide new information about minke whale calling behavior in what is likely a breeding area.Publisher PDFPeer reviewe

More Trade for Better Health? - International Trade and Tariffs on Health Products

The main objective of this paper is to analyse trade flows and tariff policies of health products. Compared to previous studies, we not only focus on medicines, but on a large set of products that enter the public health space and can be identified in the common trade classification. The first contribution is thus to construct three groups of health products based on the 2007 Harmonized System classification of international trade. Using these commodity groups, we analyse trade flows between 167 countries for the years 1996 to 2009. We find that trade in health products has developed very dynamically, with trade in dosified medicine displaying the strongest growth with an annual growth rate of almost 12 per cent. The results further indicate that the market of health products is dominated by a small number of developed countries. Looking at tariffs on health products for developed and developing countries as well as LDCs and transition economies we find that the overall level of tariffs is low, but far from being zero, especially in the last three country groups. Finally, studying the tariffs on health products in preferential trade agreements between developing countries, the results show that the tariff level is low, but in some individual cases still substantive

The Lombard effect in singing humpback whales : source levels increase as ambient ocean noise levels increase

Funding: Office of Naval Research (Code 322, Marine Mammals and Biology), Commander, U.S. Pacific Fleet (Code N465JR), and the Naval Facilities Engineering Command Living Marine Resources Program.Many animals increase the intensity of their vocalizations in increased noise. This response is known as the Lombard effect. While some previous studies about cetaceans report a 1 dB increase in the source level (SL) for every dB increase in the background noise level (NL), more recent data have not supported this compensation ability. The purpose of this study was to calculate the SLs of humpback whale song units recorded off Hawaii and test for a relationship between these SLs and background NLs. Opportunistic recordings during 2012-2017 were used to detect and track 524 humpback whale encounters comprised of 83 974 units on the U.S. Navy's Pacific Missile Range Facility hydrophones. Received levels were added to their estimated transmission losses to calculate SLs. Humpback whale song units had a median SL of 173 dB re 1 μ Pa at 1 m, and SLs increased by 0.53 dB/1 dB increase in background NLs. These changes occurred in real time on hourly and daily time scales. Increases in ambient noise could reduce male humpback whale communication space in the important breeding area off Hawaii. Since these vocalization changes may be dependent on location or behavioral state, more work is needed at other locations and with other species.Publisher PDFPeer reviewe

Is Aid for Trade Effective? A Quantile Regression Approach

This paper investigates whether Aid for Trade (AfT) improves export performance, i.e. does AfT lead to greater exports? Using panel data and panel quantile regression, our results suggest that overall AfT disbursements promote the export of goods and services mainly for the .50 and .75 quantiles. Our results also show that for some types of AfT this effect essentially vanishes at the lower tail of the conditional distribution of exports. Hence, countries that export more in volume are those benefiting most from AfT. We also investigate which types of AfT are effective. In particular, we find that aid used to build production capacity is effective. This type of aid is associated with higher exports for almost all quantiles, with the effect increasing at the upper tail of the conditional distribution. Aid used to build infrastructure is also found to affect exports at the upper tail of the distribution. In contrast, aid for trade policy and aid disbursed for general budget support (an untargeted type of aid) are not associated with greater export levels. This finding holds true irrespective of the quantile

Endogenous Product Differentiation, Market Size and Prices

Recent empirical evidence suggests that prices for some goods and services are higher in larger markets. This paper provides a demand-side explanation for this phenomenon when firms can choose how much to differentiate their products in a model of monopolistic competition with horizontal product differentiation. The model proposes that consumers love of variety makes them more sensitive to product differentiation efforts by firms, which leads to higher prices in larger markets. At the same time, endogenous product differentiation modeled in this way can lead to a positive and concave relationship between market size and entry

Mercury release and speciation in chemical looping combustion of coal

In the in situ Gasification Chemical Looping Combustion of coal (iG-CLC), the fuel is gasified in situ in the fuel reactor and gasification products are converted to CO2 and H2O by reaction with the oxygen carrier. This work is the first study on mercury release in Chemical Looping Combustion of coal. The fraction of the mercury in coal vaporized in the fuel reactor depended mainly on the fuel reactor temperature and the coal type. In the fuel reactor, mercury was mainly emitted as Hg0 in the gas phase and the amount increased with the temperature. In the air reactor, mercury was mostly emitted as Hg2+. In a real CLC system, mercury emissions to the atmosphere will decrease compared to conventional combustion as only mercury released in the air reactor will reach the atmosphere. However, measures should be taken to reduce Hg0 in the CO2 stream before the purification and compression steps in order to avoid operational problems.The authors thank the Government of Aragón and La Caixa (2012-GA-LC-076 project) and the Spanish Ministry for Science and Innovation (ENE2010-19550 project) for the financial support. P. Gayán thanks CSIC for the financial support of the project 201180E102. The authors also thank to Alcoa Europe-Alúmina Española S.A. for providing the Fe-enriched sand fraction used in this work. G. Galo is acknowledged for his contribution to the experimental results.Peer reviewe

A Short-Run Analysis of Exchange Rates and International Trade with an Application to Australia, New Zealand, and Japan

The information and communication technology (ICT) revolution of the past 3 decades has transformed the world into an integrated marketplace. Today, producers and consumers alike are able to compare the prices of local businesses and worldwide sellers. For an increasing number of tradable goods, they can take advantage of arbitrage opportunities between online and offline transactions. One of the key exogenous elements behind this arbitrage is exchange rate movements. The existing literature on exchange rates has concluded that nominal prices can be assumed to be rigid, which thus opens the door to short-term international arbitrage. However, empirical evidence of international short-term arbitrage has so far been lacking due to data constraints. In this paper, we first present a new dataset that holds records on daily international exchanges of goods, namely those sent through the international postal logistics network. We then combine this data set with daily data on international exchange rate movements to test the hypothesis of international arbitrage. Applying different econometric techniques, we show that in an environment of floating exchange rates, almost instantaneous short-term international arbitrage is indeed occurring and that it has a persistent effect. The effect seems to be particularly pronounced in the developed countries of Asia and the Pacific