Cetaceans - Science topic

Reuben Osei

Thankyou very much. Is there any webpage that has easy to follow code for metamean. also I'm not sure if I can actually do a statistical test on the results as PCB'S are made up of different parts which not all studies look at the same ones

Juan Tomas Camejo, MSc

Expert in PCR. Research IDIAF.

Dominican Republic.

If you have a morphological approximation of the possible parasites, then you should have a primer made of those species of parasites. Then DNA extraction from the eggs, which can be with a protocol for tissue and subsequently PCR with the primers of the parasite to be searched for.

I can provide some general information about cephalopod beak identification in the Eastern Central Atlantic.

Cephalopods are a group of marine animals that include squids, octopuses, and cuttlefish. They are known for their highly advanced nervous systems and complex behavior, as well as their distinctive beaks, which are used for feeding and defense. Beak identification is a common technique used by biologists and other researchers to study cephalopods, as the beak can provide important information about the species, size, and age of the animal.

There are several methods that can be used to identify cephalopod beaks, including morphometric analysis, microscopic examination, and DNA analysis. Morphometric analysis involves measuring the physical characteristics of the beak, such as its size, shape, and surface features, in order to distinguish between different species. Microscopic examination involves using a microscope to examine the internal structure of the beak and look for distinctive features that are characteristic of different species. DNA analysis involves extracting DNA from the beak and using genetic techniques to identify the species.

In the Eastern Central Atlantic, a number of different species of cephalopods can be found, including squids, octopuses, and cuttlefish. Beak identification can be a useful tool for studying these animals and understanding their biology and ecology. However, it is important to note that beak identification can be a complex and specialized field, and it may require specialized training and equipment to accurately identify cephalopod beaks.

Dear Silvia,

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I agree with Michael. See our review on turbine noise just out today and attached. The noise is entirely low frequency and not louder than passing ships. In areas with high ambient noise (also from ships), such as the North Sea, it is unlikely tha the turbine noise is even audible to whales unless very close to the turbines.

ftp://ftp.ais.dk/ais_data/

Here is a recent 2020 publication on Indonesia gillnet bycatch, published in the journal Endangered Species Research:

Physeter skull, not fully-developed animal

I think it's not a cetacean vertebra, it's probably cow vertebra according the anatomical features of the processes.

Perhaps after more cleaning and clearer images the definition be more accurate.

A simple 120 lbs recurve crossbow will do it, 150lbs max. You should find it in any fish/hunting stores, or online. No need for scope or other acessories, so it shouldn't cost more than 80-100 dollars. There are several inexpensive brands with similar looking crossbows (Buffalo River, Mankung Kantas, etc..). You may want to get an extra bow and strings to replace eventually, depending on how much you will use it. But you will have to buy the darts separately. You will need arrows with a float and biosy tips specifically designed for this (around 40mm length). Don't forget the permits for biopsying :). I hope this helps.

Your data seems to be counts and times with set times and variable counts. You need to FIRST determine what combination of the data you wish to test, one or more statistics (eg rate for y14 minus y17 or ratio). Then assume a constant rate over time and species (or for some divisions eg species). Using this rate get Poisson samples for each of time intervals, to make multiple reproductions of the data under assumption of constant rate. Calculate statistic(s) for each reproduction and sort to get the cumulative distribution, to compare with data statistic(s).

Thanks Nicholas. It's very useful. Highly appreciated!

The sighting data were recorded for almost 10 years, some in degrees and some other in UTM. But it's OK to project them in one format.

I wonder the same question. We are in the process to update our project as we are going to start this year. As part of the disease research component, we will pursue the molecular screening of pathogens in skin biopsies to investigate Paracoccidioides brasiliensis, which has now been postulated as the probable cause of lacaziosis/lobomycosis, and it has been referred to as paracoccidi­oidomycosis ceti (please, see paper by Vilela et al. 2016), in which one of our colleagues (Patricia Fair) has been involved. Only one well-documented study shows the uncultivated nature of the pathogen Lacazia loboi causing cu­taneous granulomas in dolphins (Schaefer et al. 2016). I my country (Ecuador) there is not a concerted microbiological and molecular clinical assessment to isolate and detected this pathogen from bottlenose dolphins exhibiting this kind of fungal lesions on the skin. We have observed these lesiones in the dolphins from El Morro Mangrove Reserve (Alava and Jimenez 2014) and we are aware of the overview and epidemiological studies in other sites within the Gulf of Guayaquil (Van Bressem et al. 2007; Van Brseem et al 2015). Thus, this is part the rationale to conduct this research, in addition to assessing persistent organic pollutants (POPs) and mercury.

References

Vilela, R., Bossart, G.D., Leger, J.A.S., Dalton, L.M., Reif, J.S., Schaefer, A.M., McCarthy, P.J., Fair, P.A. and Mendoza, L., 2016. Cutaneous granulomas in dolphins caused by novel uncultivated Paracoccidioides brasiliensis. Emerging infectious diseases, 22(12), p.2063.

Schaefer AM, Reif JS, Guzmán EA, Bossart GD, Ottuso P, Snyder J, et al. 2016. Toward the identification, characterization and experimental culture of Lacazia loboi from Atlantic bottlenose dolphin (Tursiops truncatus). Med Mycol. 4:659–665. http://dx.doi.org/10.1093/mmy/myw011

Gracias!!

Juan Jose Alava

Thanks Christopher for your input. Highly appreciated.

The depredation caused in the Mediterranean artisanal fisheries by the bottlenose dolphin Tursiops truncatus) is well described in the literature.

Rocklin D., Santoni M.-C., Culioli J.-M., Tomasini J.-A., Pelletier D. and D. Mouillot (2009) Changes in the catch composition of artisanal fisheries attributable to dolphin depredation in a Mediterranean marine reserve. ICES Journal of Marine Science 66 (4):699–707.

Pennino, M.G., Rotta, A., Pierce, G.J. et al. (2015). Interaction between bottlenose dolphin (Tursiops truncatus) and trammel nets in the Archipelago de La Maddalena, Italy. Hydrobiologia, 747 (1):69-82.

One possible mitigation method to this depredation is the use of acoustic pingers (with varying results).

Waples D.M., Thorne L.H., Hodge L.E.W, Burke E.K., Urian K.W. and A.J. Read (2013). A field test of acoustic deterrent devices used to reduce interactions between bottlenose dolphins and a coastal gillnet fishery. Biological conservation, 157:153-171.

In India, according to Sutaria and al. (2015), humpback dolphins of the genus Sousa, are known to cause damage and depredation of fish catch of certain fishing gears, making them unpopular, along many coastal sites.

Sutaria D., Panicker D., Jog K., Sule M., Muralidharan R. and I. Bopardikar I. (2015). Humpback Dolphins (Genus Sousa) in India: An Overview of Status and Conservation Issues. Adv Mar Biol., 72:229-56.

Zollett E. A. and A. J. Read (2006). Depredation of catch by bottlenose dolphins (Tursiops truncatus) in the Florida king mackerel (Scomberomorus cavalla) troll fishery. Fishery Bulletin, 104 (3)

Sperm whales and killer whale exert significant depredation on Patagonian toothfish caught by longline gear around Chile and Crozet Islands (Hucke-Gaete and al., 2004 ; Tixier and al., 2010 ; Tixier, 2012)

Hucke-Gaete, R., C. A. Moreno, and J. Arata. 2004. Operational interactions of sperm whales and killer whales with the Patagonian toothfish industrial fishery off southern Chile. CCAMLR Science 11:127-140.

Tixier, P. (2012). Déprédation par les orques (Orcinus orca) et les cachalots (Physeter macrocephalus) sur les palangriers à la légine australe dans le ZEE de l’archipel de Crozet. Sciences de l’environnement. Université Aix-Marseille II, 2012. Français.<tel-00910893>

Tixier, T., Gasco, N., Duhamel, G., Viviant, M., Authier, M. and C. Guinet (2010). Interactions of Patagonian toothfish fisherIes with killer and sperm whales in the crozet Islands exclusive economic zone: an assessment of depredation levels and insights on possible mitigation strategies. CCAMLR Science, 17:179–195

Secchi, E. R., and T. Vaske Jr. 1998. Killer whale (Orcinus orca) sightings and depredation on tuna and swordfish longline catches in Southern Brazil. Aquat. Mamm. 24(2):117-122.

Thank you for all your answers. Before going further, I need to consider all your  good advices and redefine my objectives more accurately before going further. I will let you know what emerges from my reflexions.

Until the late 1800s, little was known about the oceans. Folklores and myths conjured up images of terrifying sea monsters like the Norwegian kraken, and the science fiction author Jules Verne imagined that the heart of the ocean could contain "huge specimens of life from another age". But most scientists thought the darkness and cold would make the deep sea uninhabitable.

No experience with Vemco, but I would remind that "harm" is not limited to a lethal result. There is a a full range including also complete, to partial hearing loss, vocal shifting responses and sleeping disorders. Noise effects would depend on the sound pressure level as well as the exposure time to the noise.

A quick check on Vemco's website shows devices both receivers (passive) as well as transmitters (active). On the acoustic transmitters tag section, their freq are 69 kHz and 180kHz with an intensity ranging from 136dB to 162dB. I do not see much of a risk of overlapping with vocal repertoire compared with a probable partial overlapping with echolocation; however with these intensity levels, I would not consider attaching these devices (transmitters) to any cetacean.

Depending on your goals, there are alternatives to active acoustics, like passive tags or loggers that can record diverse type of data and detach from the individual after some time.

there are estensive reports of Sperm whale stranded in shallow waters in Adriatic sea. Last one was a young male of 9 m close to Rimini few years ago

Try adding one or two layers of coffee filters in your hand-held net (assuming that is what you use to scoop the whale poop). You then take the filters with the faeces out and add new layers for the next sampling. Try it out first with a VERY ripe tomato that you squeeze in a bath tub, to mimic the whale poop floating in the sea...

Juan,

It is obviously possible to find marine fossils preserved in volcanic ash layers. As other colleagues have already said, it is not a frequent feature at all, and there is a possibility to achieve special preservation conditions that may lead to a fossil lagerstatte, so you should pay attention to the preservation of the faunal content. About the concretions, I cannot find any clear evidence of volcanic origin, but volcanic ashes have a certain potential for natural cementation, and they might be actively involved in sedimentary processes leading to lithification. You can find an example of Ordovician marine beds made of volcanic ashes in this reference here in Researchgate:

Calcareous K-bentonite deposits in the Utica Shale and Trenton Group (Middle Ordovician), of the Mohawk Valley, New York State

You may find many references regarding marine sediments and rocks composed of volcanic ashes. Good luck with your search!

Juan

Yes, it can be done. You can increase the success of your analysis by (i) taking multiple skin samples from different parts of the body, (ii) take the skin sample from as deep in the skin as possible (deeper = less UV damage), (iii) amplify short DNA fragments, (iv) optimize your primers for the relevant species.

If possible, try to sample other types of tissue as well.

See Luksenburg et al. (2015) for an example. We obtained DNA from samples that had been exposed to tropical heat for weeks/months and got good results.

Luksenburg, JA, Henriquez, A & Sangster, G 2015. Molecular and morphological evidence for the specific identity of Bryde’s Whales in the southern Caribbean. Marine Mammal Science 31: 1568–1579.

I assume you want georeferences. In that case you might consider geoserver (geoserver.org), coupled with a postgis database. You can find lot of implementations of this kind: for one, you can use OpenShift to develop this for free. Is this what you are looking for?

Rats were fed with 1 ppm in water for one year and found kidney damage, visible brain damage, a greater uptake of aluminium into the brain, and beta-amyloid deposits which have been associated with Alzheimer’s disease.

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The bioavailability of aluminium in drinking water is low and thus the contribution from drinking water is low compared to other dietary sources and thus of little significance or concern. Aluminium can occur in detectable levels in many natural water sources and generally arises from aluminium containing soils. The most common source in public water supplies arises from the use of Aluminium-based coagulants in the water purification process. Water suppliers aim to maintain a level below 0.1 mg/L with the focus being on ensuring the aesthetic quality of the water. Concerns have been expressed as whether aluminium in drinking water might pose a neurotoxic risk as aluminium is present in Alzheimer plaques in the brain tissue of people with Alzheimer’s Disease. As a precautionary measure the aluminium content of water used in renal dialysis is maintained below 0.01mg/L (ADWG). There is however no convincing evidence of neurotoxic effects at levels detected in the tankwater. 

Since you don't have photos, it's difficult to know what the cause of the condition you mention. However, the video and photo from Simon seems to me to be stalked barnacles. They have been described in many cetaceans, and I've found in franciscanas (Pontoporia blainvillei) from my area. You can see a photo of it at https://flic.kr/p/rPR6qt

Are these helpful?

You may be interested to read my publication on this topic. We are currently in year 3 of this 5-year study, if you have any other questions please message me. 

I agree with Marc - the tissues are essentially unrelated. If you are thinking about the transition to filter feeding in mysticetes then you might start with these papers (below) or a popular book on whale evolution - there are several by Berta, Thewissen, DR Wallace and others.

Deméré, Thomas A., et al. "Morphological and molecular evidence for a stepwise evolutionary transition from teeth to baleen in mysticete whales." Systematic Biology 57.1 (2008): 15-37.

A bizarre new toothed mysticete (Cetacea) from Australia and the early evolution of baleen whales. Erich M.G Fitzgerald Proc. R. Soc. B: 2006 273 2955-2963; DOI: 10.1098/rspb.2006.3664. Published 7 December 2006

Hi Bruno, no doubt about it. This individual presents the remains of a propeller strike of at least two years old (the scar is not longer whitish). I have seen these wounds quite frequently in Chilean Patagonia with the increasingly busy fjords due to the salmon farm expansion. I have several photos just like this one but mainly on L. australis. Despite the photo is not very big, you can see at least four contact points all separated by the same distance. Your photo is great since it almost replicates the position the dolphin had a second before the collision happened. The cuts are at the same distance but the two biggest are also at the same depth. They are not in straight lines but slightly curved both in the same manner regardless of the amount of mass involved (active source).

In contrast, in my experience net wounds tend to be located at the closest section to the flukes and frequently they include longitudinal cuts on the flukes themselves. The net slides back since the peduncle gets thinner towards the tail but then can get stuck on the tail producing the cuts at that level. The lesions of this individual are not grouped close to the tail but positioned at same distance from each other regardless of the thickness of the peduncle. Also the cuts from the surface (dorsum) present a forward direction. They are not even vertical but towards the front of the individual. Whatever did these cuts, had "its own energy" in order to achieve that direction and the high speed needed as well to counterfeit the movement of the dolphin. Anybody with experience performing necropsies on cetaceans can confirm how hard is to cut at this level of the body. The tissue is very dense. These lesions are not due to a passive source. Nets tend to produce only a superficial damage unless getting stuck on structures like flippers or the tail due to their dragging effect. Therefore the cuts, when due to nets, tend to cut towards the back of the affected individual.

In conclusion, considering the direction of the wounds, their period, number and slight curved shape, we have no nets here but the "classic" small propeller blade wounds in perhaps the most frequent site where dolphins get these lesions. I am always surprised how some individuals can survive and keep up with these wounds but at the same time we do not know the rate of mortality. Perhaps these cases of survival are only a small percentage. We simply do not know.

It is important to report these collision cases to IWC and IMO since there is a worldwide database collecting information about this threat to both wildlife and vessels. Speed and/or path restrictions can be implemented in areas with high rates of collisions. Governments are required to report these cases to IMO but the details of this procedure depend on each country.

I recommend you to check some of the pics we posted in this paper:

kind regards

Dear colleagues, MTSG web page (link below) include the last assessment done in 2013, using leatherback subpopulations: The text of the MTSG is "Globally, leatherback status is now Vulnerable. East Pacific, West Pacific, Southwest Atlantic, and Southwest Indian Ocean subpopulations were listed as “Critically Endangered,” Northwest Atlantic leatherbacks were listed as “Least Concern,” and Northeast Indian Ocean and Southeast Atlantic subpopulations were listed as “Data Deficient.”

Long ago sperm whale click were called carpenter fish sounds. 

Sure.

There are many studies that used stable isotope of C and N isotopes for this.

Best and Schell (1996) with stable isotopes of carbon and nitrogen indicated the seasonal movements for southern right whale Eubalaena australis.

Ontogenetic migration of maturing and mature male of sperm whale Physeter macrocephalus to high latitude by segregating from natal groups in low latitudes, which was apparent but not conclusive for long, was decoded by Mendes et al. (2007) through stable isotope ratios of carbon and nitrogen from dentine collagen.

There are several other studies also, especially of Turtles, that underscored their migratory dependencies.

Migratory dichotomy, practiced by the sea turtles to understand their behaviour, ecology and demography. Zbinden et al. (2011) though the aid of stable nitrogen isotope discriminated the two foraging regions area preferred by the loggerhead seas turtle Caretta caretta in the Mediterranean region to understand the relative importance of geographically separated foraging regions and associated phenotypic variations accruing from this discrimination.

Similar, but ontogenetic dietary based oceanic–to–neritic migration has been confirmed by McClellan et al (2010) for juvenile loggerhead sea turtles, which has important bearing for the loggerhead individual survivorship, stage duration and time of maturity.

1. Best, P. B., & Schell, D. M. (1996). Stable isotopes in southern right whale (Eubalaena australis) baleen as indicators of seasonal movements, feeding and growth. Marine Biology, 124(4), 483-494.

2. Mendes, S., Newton, J., Reid, R. J., Zuur, A. F., & Pierce, G. J. (2007). Stable carbon and nitrogen isotope ratio profiling of sperm whale teeth reveals ontogenetic movements and trophic ecology. Oecologia, 151(4), 605-615.

3. Zbinden, J. A., Bearhop, S., Bradshaw, P., Gill, B., Margaritoulis, D., Newton, J., & Godley, B. J. (2011). Migratory dichotomy and associated phenotypic variation in marine turtles revealed by satellite tracking and stable isotope analysis. Marine Ecology Progress Series, 421, 291-302.

4. McClellan, C.M., Braun–McNeil, J. Avens, L., Wallace, B.P. and Read, A.J. 2010. Stable isotopes confirm a foraging dichotomy in juvenile loggerhead sea turtles. J Experiment Mar Biol Ecol, 387, 44–51.

Also follow K.A. Hobson work related with tropic linkages

I would recommend considering PeerJ (peerj.com).

They are fully open access, fast (~ 3 weeks to respond) , inexpensive (pay a one time $99 fee and publish for free for the rest of your career), indexed (pubmed etc) . No impact factor yet (started last year) but rapidly growing.

Armin, thank you for the information, much appreciated.

As long as you can randomize the group selection (i.e. you don't select groups because they are easy to see or apparent because they are doing something interesting), focal group sampling with ad libitum could certainly work. It all depends on your questions and hypotheses of course. Good luck!

Hi Christina, I have been working with bottlenose dolphin burst pulsed sounds during the last years and I understand your need to find to define the differences between sounds. The existing literature is vague because burst pulses have been traditionally discussed in terms of their sonic properties and is difficult to measure when calls are classified solely by ear or acoustic features. Terms such as “screeches,” “gulps”, “brays”, "barks", “quacks”, “yelps”, and more… commonly used to describe and distinguish burst pulsed sounds can result in misleading conclusions, as they primarily describe the subjective impressions experienced by human listeners. Additionally, the way the vocalizations are analyzed, and the authors tendency to split or lump, also affects the interpretation of repertoire size. For example, a bray is formed by two different types of burst pulsed sounds however a bark is only one... In one of my studies I have classified the burst pulses based on the duration of the sound (in the oscillogram), in other studies I also measured the Interclick interval or interpulse interval manually (for this I have used a software called soundruler).

As a start, I suggest you to form classes of burst pulsed sounds on the basis of structural characteristics (for example I used the duration), this would lead to more meaningful comparisons between categories.

Good luck!

I would not characterize coastal delphinids as 'apex' predators since they are merely piscivores and the dolphins themselves are subject to predation by sharks. Although it is true that delphinids may serve as sentinel species for the health of an ecosystem, their diet is too dynamic to make broad sweeping statements. See publications by Dr Nelio Barros.

Here is a paper from the Adriatic Sea that may be of help.