Vocal repertoire and acoustic behavior of the isolated AT1 killer whale subpopulation in southern Alaska

2005 ◽  
Vol 83 (8) ◽  
pp. 1015-1029 ◽  
Author(s):  
Eva L Saulitis ◽  
Craig O Matkin ◽  
Francis H Fay
Keyword(s):  
West Coast ◽  
Gulf Of Alaska ◽  
High Amplitude ◽  
Foraging Strategy ◽  
Vocal Repertoire ◽  
Acoustic Behavior ◽  
Killer Whales ◽  
Long Distance ◽  
The North ◽  
Context Specific

Killer whales, Orcinus orca (L., 1758), in the North Pacific are classified as three genetically distinct ecotypes: residents (fish-eaters), transients (mammal-eaters), and offshores (probable fish-eaters). Within the transient ecotype, three putative subpopulations have been identified by genetic analysis: West Coast transients, Gulf of Alaska transients, and AT1 transients. Here, we examine the behavior and vocalizations of the AT1 transients, which are found only in the Prince William Sound/Kenai Fjords region, to determine if their acoustic behavior distinguishes them from other genetically distinct transient subpopulations. We identified 14 discrete, pulsed calls in the vocal repertoire of the AT1 transients. These calls were entirely different than those of West Coast and sympatric Gulf of Alaska transients. Despite their large call repertoire, AT1 transients were silent most of the time, utilizing a foraging strategy of stealth, acoustic crypsis, and passive listening for locating marine-mammal prey. Unlike resident killer whales, AT1 transient vocalization types were context specific. For example, lone AT1 transients produced long-distance, high-amplitude pulsed calls in stereotyped sequences to locate other AT1 whales. In contrast, hunting individuals emitted low-amplitude pulsed calls to maintain contact with group members. The repertoire and call-usage patterns of the AT1 transients are consistent with genetic evidence that they are a unique, reproductively and socially isolated subpopulation in danger of extinction.

The occurrence of shearwaters (Puffinus spp.) off the west coast of Canada

1983 ◽  
Vol 61 (9) ◽  
pp. 2064-2077 ◽  
Author(s):  
Juan R. Guzman ◽  
M. T. Myres
Keyword(s):  
British Columbia ◽  
Continental Shelf ◽  
West Coast ◽  
North Pacific ◽  
Gulf Of Alaska ◽  
Washington State ◽  
The West ◽  
The North ◽  
The Relationship ◽  
The North Pacific

Shearwaters, Puffinus spp., were studied off the west coast of Canada from 1975 to 1978. Sooty shearwaters, P. griseus, were the most abundant shearwaters off British Columbia in both May and September–October. Pink-footed shearwaters, P. creatopus, also occurred in both spring and fall. Flesh-footed shearwaters, P. carneipes, were found only in May. Buller's shearwaters, P. bulleri, were encountered in June and July during cruises across the Gulf of Alaska and in September and October off British Columbia. The recent increase of Buller's shearwater in the North Pacific is documented. A review of records of the short-tailed shearwater, P. tenuirostris, shows that it is usually rare and irregular off the coast of British Columbia. One black-vented shearwater, P. opisthomelas, was seen in the Gulf of Alaska. Sooty shearwaters occur off British Columbia in far lower numbers than off northern California, Oregon or Washington State. The manner in which sooty shearwaters migrate is described. The relationship between shearwater distributions and depths of water over the continental shelf are examined.

scholarly journals Vocal repertoire, harmonic structure, and behavioural context in Red-throated Loon (Gavia stellata)

2021 ◽  
Vol 135 (2) ◽  
pp. 165-180
Author(s):  
Sheila D. Douglas ◽  
Thomas E. Reimchen
Keyword(s):  
Low Frequency ◽  
High Amplitude ◽  
Breeding Birds ◽  
Vocal Repertoire ◽  
Sexually Dimorphic ◽  
Harmonic Structure ◽  
Freshwater Lakes ◽  
Haida Gwaii ◽  
Context Specific ◽  
Frequency Harmonic

Among the five loon species (Gaviidae), Red-throated Loon (Gavia stellata) is the oldest lineage and is the most divergent in morphology and vocalizations. We substantially expand earlier description of calls for a nesting pair and non-breeding birds on Haida Gwaii, British Columbia, Canada. Three major calls used by the nesting pair (Quack, Wail, Plesiosaur) were all low frequency (700–3000 Hz) with multiple harmonics, calls that were also used by non-breeding birds without territories that overnight on freshwater lakes. Call duetting in the Wail and Plesiosaur, as well as sexually dimorphic frequencies and structure within the duets, typically occur in territorial display or pair interactions. The nesting pair used several calls audible only at short distances (Coo, Extended Coo, Staccato, Soft Raack) that were low frequency (200–1200 Hz), graded in behavioural intensity and that resulted in chick responses, including feeding or return to nest. A high amplitude Loud Raack was used by the female and is associated with flight incentives for pre-fledged chicks. Vocalizations of chicks, usually feeding solicitations to the adults, develop from simple chirps in the first week following hatch to more complex calls resembling the Wail and the Plesiosaur calls just prior to fledging. Although the majority of our acoustical descriptions are limited to a single nesting pair where sexes could be differentiated, these represent the first quantification of sound frequency, harmonic structure, and duration, most often associated with context-specific responses, and are suggestive of syntactical content to the vocal repertoire of this basal taxon.

scholarly journals Passive acoustic monitoring of killer whales (Orcinus orca) reveals year-round distribution and residency patterns in the Gulf of Alaska

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hannah J. Myers ◽  
Daniel W. Olsen ◽  
Craig O. Matkin ◽  
Lara A. Horstmann ◽  
Brenda Konar
Keyword(s):  
Killer Whale ◽  
Marine Ecosystem ◽  
Distribution Patterns ◽  
Gulf Of Alaska ◽  
Acoustic Monitoring ◽  
Orcinus Orca ◽  
Killer Whales ◽  
Passive Acoustic Monitoring ◽  
The North ◽  
Passive Acoustic

AbstractKiller whales (Orcinus orca) are top predators throughout the world’s oceans. In the North Pacific, the species is divided into three ecotypes—resident (fish-eating), transient (mammal-eating), and offshore (largely shark-eating)—that are genetically and acoustically distinct and have unique roles in the marine ecosystem. In this study, we examined the year-round distribution of killer whales in the northern Gulf of Alaska from 2016 to 2020 using passive acoustic monitoring. We further described the daily acoustic residency patterns of three killer whale populations (southern Alaska residents, Gulf of Alaska transients, and AT1 transients) for one year of these data. Highest year-round acoustic presence occurred in Montague Strait, with strong seasonal patterns in Hinchinbrook Entrance and Resurrection Bay. Daily acoustic residency times for the southern Alaska residents paralleled seasonal distribution patterns. The majority of Gulf of Alaska transient detections occurred in Hinchinbrook Entrance in spring. The depleted AT1 transient killer whale population was most often identified in Montague Strait. Passive acoustic monitoring revealed that both resident and transient killer whales used these areas much more extensively than previously known and provided novel insights into high use locations and times for each population. These results may be driven by seasonal foraging opportunities and social factors and have management implications for this species.

The Scottish Herring Trade, 1470–1600

2005 ◽  
Vol 84 (2) ◽  
pp. 149-165 ◽  
Author(s):  
Martin Rorke
Keyword(s):  
Sixteenth Century ◽  
West Coast ◽  
North West ◽  
Capital Costs ◽  
The North ◽  
East And West

This paper uses customs figures to show that herring exports from the east and west coast lowlands expanded significantly in the last six decades of the sixteenth century. The paper argues that the rise was primarily due to the north-west Highland fisheries being opened up and exploited by east and west coast burghs. These ventures required greater capital supplies and more complex organisation than their local inshore fisheries and they were often interrupted by political hostilities. However, the costs were a fraction of those required to establish a deepwater buss fleet, enabling Scotland to expand production and take advantage of European demand for fish while minimising additional capital costs.

Maritime and River Traders, Landing Places, and Emporia Ports in the Merovingian Period in and Around the Low Countries

2020 ◽  
pp. 763-796
Author(s):  
Dries Tys
Keyword(s):  
North Sea ◽  
Institutional Economics ◽  
New Institutional Economics ◽  
Central Position ◽  
Economic Activities ◽  
Early Medieval ◽  
Low Countries ◽  
Long Distance ◽  
The North ◽  
The North Sea

The origin, rise, and dynamics of coastal trade and landing places in the North Sea area between the sixth and eighth centuries must be understood in relation to how coastal regions and seascapes acted as arenas of contact, dialogue, and transition. Although the free coastal societies of the early medieval period were involved in regional to interregional or long-distance trade networks, their economic agency must be understood from a bottom-up perspective. That is, their reproduction strategies must be studied in their own right, independent from any teleological construction about the development of trade, markets, or towns for that matter. This means that the early medieval coastal networks of exchange were much more complex and diverse than advocated by the simple emporium network model, which connected the major archaeological sites along the North Sea coast. Instead, coastal and riverine dwellers often possessed some form of free status and large degrees of autonomy, in part due to the specific environmental conditions of the landscapes in which they dwelled. The wide estuarine region of the Low Countries, between coastal Flanders in the south and Friesland in the north, a region with vast hinterlands and a central position in northwestern Europe, makes these developments particularly clear. This chapter thus pushes back against longstanding assumptions in scholarly research, which include overemphasis of the influence of large landowners over peasant economies, and on the prioritization of easily retrievable luxuries over less visible indicators of bulk trade (such as wood, wool, and more), gift exchange, and market trade. The approach used here demonstrates that well-known emporia or larger ports of trade were embedded in the economic activities and networks of their respective hinterlands. Early medieval coastal societies and their dynamics are thus better understood from the perspective of integrated governance and economy (“new institutional economics”) in a regional setting.

First record of Norwegian killer whales attacking and feeding on a harbour porpoise

2015 ◽  
Vol 8 ◽  
Author(s):  
A. Mel Cosentino
Keyword(s):  
North Atlantic ◽  
Marine Mammals ◽  
First Record ◽  
Harbour Porpoise ◽  
Sperm Whales ◽  
Killer Whales ◽  
Strait Of Gibraltar ◽  
Cetacean Species ◽  
The North ◽  
Northern Bottlenose Whales

Orcinus orcais a cosmopolitan species and the most widely distributed marine mammal. Its diet includes over 140 species of fish, cephalopods, sea birds and marine mammals. However, many populations are specialised on certain specific prey items. Three genetically distinct populations have been described in the North Atlantic. Population A (that includes the Icelandic and Norwegian sub-populations) is believed to be piscivorous, as is population C, which includes fish-eating killer whales from the Strait of Gibraltar. In contrast, population B feeds on both fish and marine mammals. Norwegian killer whales follow the Norwegian spring spawning herring stock. The only description in the literature of Norwegian killer whales feeding on another cetacean species is a predation event on northern bottlenose whales in 1968. Daily land-based surveys targeting sperm whales were conducted from the Andenes lighthouse using BigEyes®binoculars (25×, 80 mm). The location of animals at sea was approximated through the use of an internal reticule system and a graduated wheel. On 24 June 2012 at 3:12 am, an opportunistic sighting of 11 killer whales was made off Andenes harbour. The whales hunted and fed on a harbour porpoise. Despite these species having overlapping distributions in Norwegian waters, this is the first predatory event reported in the literature.

scholarly journals Geochemical and isotopic evidence of groundwater salinization processes in the Essaouira region, north-west coast, Morocco

2021 ◽  
Vol 3 (7) ◽  
Author(s):  
Otman EL Mountassir ◽  
Mohammed Bahir ◽  
Driss Ouazar ◽  
Abdelghani Chehbouni ◽  
Paula M. Carreira
Keyword(s):  
Groundwater Recharge ◽  
West Coast ◽  
Exchange Process ◽  
Environmental Isotopes ◽  
Annual Rainfall ◽  
Groundwater Salinization ◽  
Rock Interaction ◽  
North West ◽  
The North ◽  
Water Rock Interaction

AbstractThe city of Essaouira is located along the north-west coast of Morocco, where groundwater is the main source of drinking, domestic and agricultural water. In recent decades, the salinity of groundwater has increased, which is why geochemical techniques and environmental isotopes have been used to determine the main sources of groundwater recharge and salinization. The hydrochemical study shows that for the years 1995, 2007, 2016 and 2019, the chemical composition of groundwater in the study area consists of HCO3–Ca–Mg, Cl–Ca–Mg, SO4–Ca and Cl–Na chemical facies. The results show that from 1995 to 2019, electrical conductivity increased and that could be explained by a decrease in annual rainfall in relation to climate change and water–rock interaction processes. Geochemical and environmental isotope data show that the main geochemical mechanisms controlling the hydrochemical evolution of groundwater in the Cenomanian–Turonian aquifer are the water–rock interaction and the cation exchange process. The diagram of δ2H = 8 * δ18O + 10 shows that the isotopic contents are close or above to the Global Meteoric Water Line, which suggests that the aquifer is recharged by precipitation of Atlantic origin. In conclusion, groundwater withdrawal should be well controlled to prevent groundwater salinization and further intrusion of seawater due to the lack of annual groundwater recharge in the Essaouira region.

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