First record of a dwarf sperm whale, Kogia sima (Owen, 1866) stranded alive along the coasts of Italy (*) (original) (raw)
Marine Mammal Science, 2006
Little is known about the feeding ecology of pygmy sperm whales (Kogia breviceps) in the Northeast Atlantic. Results are presented on the stomach contents of five whales stranded on the Galician coast (NW Spain) between 1995 and 2002 and seven whales stranded on the French Atlantic coast between 1984 and 2001. These results are compared with those obtained from the stomach contents of two pygmy sperm whales (a pregnant female and her calf ) stranded on the Scottish (UK) coast in 1999, the first records of the species in Scotland. In 13 out of 14 cases, food remains consisted almost entirely of cephalopod beaks, although some crustacean and fish remains were also present. In all the Spanish specimens, the identified prey were oceanic species: the cephalopods Histioteuthis reversa, H. bonnellii, Todarodes sagittatus, the viperfish Chauliodus sloani, and the giant mysid Gnatophausia sp. The same cephalopod species were found in the stomachs of the whales stranded in Scotland, although both whales had also consumed neritic cephalopod species such as Rossia macrosoma and other sepiolids. In the French specimens, almost all prey 600 SANTOS ET AL.: PYGMY SPERM WHALES 601 identified were oceanic cephalopods (H. reversa, Brachioteuthis riseii, T. sagittatus, Taonius pavo, etc.), but remains of crustaceans and a neritic squid (Loligo forbesi) were also found. One whale from France had eaten mainly Henslow's swimming crab (Polybius henslowi). Results from the present study are consistent with those found by other authors in the Azores and the Canary Islands in that pygmy sperm whales appear to be mainly teuthophagous, with histioteuthid squids forming an important part of the diet. Strandings records suggest that occurrence of pygmy sperm whales in the NE Atlantic may be seasonal, with most strandings occurring in autumn and winter.
The stomach contents of a male sperm whale, Physeter macrocephalus, stranded on Forte dei Marmi beach (Italy, Ligurian Sea) were examined. Food items consisted exclusively of cephalopod hard parts: 233 upper and 291 lower beaks and one fish eye lens. The majority of the identified cephalopod beaks belonged to Histioteuthis bonnellii, but a few beaks of Galiteuthis armata and Octopoteuthis sp. were also found. A new beak size -cephalopod size regression was created for H. bonnellii with specimens caught in the study area. Reconstructed prey weight for the species was much higher when applying this new regression instead of Clarke's, highlighting the need for area-and species-specific regressions for dietary studies. Our analysis represents the second report on the stomach contents of sperm whales from the Mediterranean and the first available information for the Western basin. Combining data from a multi-sensor tag and passive sonar to determine the diving behaviour of a sperm whale (Physeter macrocephalus). IEEE Journal of Oceanic Engineering 28, 13-28.
Animals
We investigated the relationship between age and body length, and age at sexual maturity of Physeter macrocephalus individuals stranded along the Italian coast. Our molecular analysis shows that all our samples belong to the C.001.002 haplotype, shared between Atlantic and Mediterranean populations. We show that males attain sexual maturity at 10 years, similar to those from other marine areas. However, considering the same body length class, Mediterranean males are older than Atlantic ones. Our finding of a Mediterranean pregnant female of only 6.5 m in length and an assessed age of 24–26 years is particularly noteworthy, considering that females reach sexual maturity at about 9 years and 9 m of total length in other regions. Comparing our results with the literature data, we highlight the positive correlation between lifespan, adult body length and weight of males from the Mediterranean and Atlantic Ocean. Regardless of whether the relatively small size of Mediterranean specimens ...
Aquatic Conservation: Marine and Freshwater Ecosystems, 2014
Boat surveys aimed at studying sperm whales in the Tyrrhenian Sea were conducted between 2002 and 2011. During 768 daily surveys, a total effort of 32 602 km was achieved within an area of 8800 km2 resulting in 92 encounters with 229 sperm whale individuals. Average encounter rates of sperm whales was 0.5 groups per 100 km2, with a higher concentration in the vicinity of the submarine canyon of Cuma, confirming the importance for the species of this small hotspot in the Mediterranean Sea. Encounter rates increased with increasing distance from the coast. It is possible that the intense boat traffic and anthropogenic disturbance in the area may be moving animals away from the coast leading to habitat loss. The species–habitat relationship documented in this study has implications for conservation. Copyright © 2014 John Wiley & Sons, Ltd.
Marine Mammal Science, 1992
Little is known about the whales occurring in the southern Caribbean (van Bree 1975). The strandings reported here are the first records of the Gervais' beaked whale and the dwarf sperm whale for the Netherlands Antilles and extend the known range of these species well into the southeastern Caribbean. Information on morphometrics and food habits are given for the stranded Gervais' beaked whale. A medium-sized cetacean was found, reportedly alive, by a beach visitor at Playa Mansalina (12"14'55"N, 69006'lO"W), San Juan, Curacao on 16 March 1990. Upon arrival at the site around noon the next day, the specimen was identified as a male Gervais' beaked whale, Mesoplodon europaeus, (Fig. 1) and was observed to be dead. The animal lay in the surf and the onset of decay was noted. Large portions of the skin had been chafed to a pale cream color possibly in the process of stranding or in part due to decay. The color was dark gray to black dorsally and gray on the sides. Scarring was extensive and included linear scars as well as some oval scars, the latter of which may have been from cookiecutter sharks (Jones 1971). The specimen did not show any signs of external injury other than a few minor punctures (e.g., Raun et al. 1970) near the anal region. Four stalked barnacles, Conchoderma auritum, were attached to the right tooth. The site was visited on several occasions to take photographs and to collect measurements and samples. In the last week of May the complete skeleton of the specimen (CPM 2.1) was collected for cleaning and has since been placed on public display in the Christoffel Park Museum, Curacao. External measurements and blubber thickness were taken to the nearest centimeter using a measuring tape. Skull measurements were taken to the nearest millimeter using calipers. All measurements were taken after Ross (1984). External measurements and blubber thickness of the specimen are presented in Table 1 while skull and tooth measurements are presented in Table 2. The right testis of the specimen weighed 44.7 g and measured approximately 78 x 32 x 27 mm (fixed in formalin and with the epididymis trimmed off). Sexual maturity was suggested by the erupted teeth. All vertebral epiphyses were fused to the centra indicating that the 425-cm-long specimen was physically mature. The vertebral formula was C7, T9, L12, Cl9 = 47, with a total of eight chevrons. The first four cervical vertebrae were fused. The fifth and sixth vertebrae 172
Journal of Experimental Marine Biology and Ecology, 2020
Cetacean stranding events are an important source of information and biological samples, providing data on species occurrence, distribution and population dynamics as well as on mortality rate induced by human activities or natural causes. This is even truer for species such as Z. cavirostris, whose elusive behavior has made its field observation difficult in many Mediterranean areas. Although the occurrence of single or serial strandings of this species and the rise in survey effort have increased the knowledge on its presence, there are still gaps in some Mediterranean areas, especially in the Gulf of Taranto (North-western Ionian Sea, Italy), where a critical habitat suitable for different cetacean species has been identified. Despite no sightings of Z. cavirostris having been recorded so far, ACCOBAMS designates the Gulf of Taranto as an Area of Special Concern for Beaked Whales (ASC-BW) on the basis of atypical mass strandings of 12 individuals which occurred in the Ionian Sea in 2011. Moreover, the conservation status of the Z. cavirostris has recently passed from Data Deficient to Vulnerable, according the IUCN criteria adopted for the Mediterranean Sea, thus showing the urgent need for basic information on its bio-ecological features, suitable habitat and threats at local or wider scale. This study is the first attempt at application in the Mediterranean Sea of a Lagrangian prediction model simulating the carcass drift trajectories to investigate the at-site sea origin of an individual of Z. cavirostris stranded in the Gulf of Taranto. Moreover, a necropsy was carried out to detect the possible cause of death and the results of bacteriological, biomolecular and toxicological analysis are provided. Finally, a collection of osteological data as well as the process of turning and displaying the skeleton in a museum are detailed, highlighting the importance of these exhibits from a scientific and educational point of view.
lafiba.org
On 17-19 November 2007, two mass stranding events of melon-headed whales Peponocephala electra occurred in western Boavista, Cape Verde Islands, concerning 265 and 70 animals respectively. Only ca. 65 individuals could be successfully returned to the sea. Dead animals were immediately buried in a mass grave on the beach which however impeded necropsies and sampling. A study visit from 9-17 January 2008 attempted to reconstruct events, collect biological data and liaise with local stakeholders for improved documenting of future stranding events. Despite advanced decomposition, 16 specimens were exhumed. Samples collected include: skulls (n=9), stomach contents (n=3) and tissue samples (n=12). Screening of photographic evidence showed tightly grouped live-strandings, with many refloated individuals beaching again. The live-strandings and the total absence of tell-tale injuries associated with fishing gear excluded fisheries interactions. Good body conditions and indications of antemortem feeding were also inconsistent with epizootic infectious disease. Finally, nothing suggests that biotoxins or chemical contamination were involved, and the cause of the strandings remains unknown. The presence of submarine USS Annapolis in Cape Verde waters, apparently coinciding temporally with the strandings, led some to raise questions about the use of active sonar. Once identified, abundant squid beaks and fish otoliths found in fore-and main stomachs will provide valuable data on the feeding ecology of melon-headed whales in the eastern Atlantic. Study of cranial and genetic variation will help delineate population structure. A cursory examination of skeletal material of other small cetaceans, including pilot whales, did not support the occurrence of long-finned pilot whale G. melas in Cape Verde.
Scientific Reports, 2018
Mass strandings of sperm whales (Physeter macrocephalus) are rare in the Mediterranean Sea. Nevertheless, in 2014 a pod of 7 specimens stranded alive along the Italian coast of the Central Adriatic Sea: 3 individuals died on the beach after a few hours due to internal damages induced by prolonged recumbency; the remaining 4 whales were refloated after great efforts. All the dead animals were genetically related females; one was pregnant. All the animals were infected by dolphin morbillivirus (DMV) and the pregnant whale was also affected by a severe nephropathy due to a large kidney stone. Other analyses ruled out other possible relevant factors related to weather conditions or human activities. The results of multidisciplinary post-mortem analyses revealed that the 7 sperm whales entered the Adriatic Sea encountering adverse weather conditions and then kept heading northward following the pregnant but sick leader of the pod, thereby reaching the stranding site. DMV infection most likely played a crucial role in impairing the health condition and orientation abilities of the whales. They did not steer back towards deeper waters, but eventually stranded along the Central Adriatic Sea coastline, a real trap for sperm whales.