Harbour Porpoises Phocoena Research Articles

Behavioral, Pathomorphological, and Clinical Observations of a Young Harbor Porpoise (Phocoena phocoena) with Congenital Hemihydranencephaly

Internal anatomical disorders in marine mammals often only become apparent during necropsies. A case of hemihydranencephaly (HHAE) in a harbor porpoise (Phocoena phocoena) is described herein. HHAE is a rare, severe congenital brain disorder whereby one cerebral hemisphere is replaced by a sac filled with cerebrospinal fluid. The harbor porpoise was a formerly stranded and rehabilitated juvenile female, exhibiting behavior during her life in captivity that fell into two distinct modes. During her normal, “active” mode, she behaved like other harbor porpoises and performed well in training sessions. During her abnormal, “passive” mode, she listed onto her left side and floated with her right side at the water surface for several minutes at a time. At least her right eye would be closed, and she appeared to be in deep sleep. While floating at the surface and tilted over, she probably occasionally inhaled small amounts of water, resulting in recurring pneumonia. Ten months after stranding, at the age of ~24 months, the porpoise suddenly died. She was diagnosed with right-sided HHAE upon necropsy, which suggests that her passive-mode behavior was abnormal sleep. Cetaceans exhibit unihemispheric sleep so that they can maintain voluntary breathing, swimming, thermoregulation, body position, and vigilance. Possessing only one cerebral hemisphere, the porpoise lost the ability to sleep in this way. Following necropsy, the proximate cause of her death was probably an extensive lung edema followed by hypoxia, but the HHAE was assumed to be the ultimate cause. This case report shows that, despite the negative outcome, HHAE in harbor porpoises can be compatible with life and may not result in the cognitive or motor impairments that are seen in some human HHAE patients.

Severe Parasitism in a Harbour Porpoise (Phocoena phocoena) Stranded in Belgium

Severe Parasitism in a Harbour Porpoise (Phocoena phocoena) Stranded in Belgium

Is Harbor Porpoise (Phocoena phocoena) Exhaled Breath Sampling Suitable for Hormonal Assessments?

Simple SummaryThe progress of animal welfare in wildlife conservation and research calls for more non-invasive sampling techniques. In cetaceans, exhaled breath condensate (blow)—a mixture of cells, mucus and fluids expelled through the force of a whale’s exhale—is a unique sampling matrix for hormones, bacteria and genetic material, among others. Especially the detection of steroid hormones, such as cortisol, is being investigated as stress indicators in several species. As the only native cetacean in Germany, harbor porpoises (Phocoena phocoena) are of special conservation concern and research interest. So far, strandings and live captures have been the only method to obtain samples from free-ranging individuals, and novel, non-invasive monitoring methods are desirable for this small cetacean species. Hence, three different blow collection devices were tested on harbor porpoises. All samples were analyzed for cortisol using a commercially available immunosorbent assay. The most suitable protocol for sampling, storage and processing is using a sterile 50 mL centrifuge tube. This pilot study shows that cortisol can be detected in the exhale of harbor porpoises, thus paving the way for future studies and most likely successful non-invasive small cetacean health monitoring through blow.Over the last decades, exhaled breath sampling has been established for laboratory analysis in various cetacean species. Due to their small size, the usability of respiratory vapor for hormone assessments was questionable in harbor porpoises (Phocoena phocoena). This pilot study compared three different blow collection devices for their suitability in the field and during laboratory processing: a sterile petri dish covered by a Nitex membrane, as well as sterile 50 mL centrifuge tubes with or without manganese(II) chloride as a stabilizer. Collected exhales varied between three, five or ten, depending on feasibility. Hormones were extracted through an ether mix, followed by centrifugal evaporation and cortisol analysis using an immunoassay. Although close to the lower end of the assay’s dynamic range, the ELISA produced results (n = 110, 0.102–0.937 ng/mL). Hence, a simple 50 mL centrifuge tube was determined as the best suited blow collection device, while three consecutive exhales proved sufficient to yield results. These findings are promising regarding the suitability of exhaled breath as a matrix for future endocrine and immune system-related studies in harbor porpoises. If further advanced, blow sampling can become an important, non-invasive tool for studying and monitoring health, stress levels and diseases in harbor porpoises.

Growth and Reproduction in Harbour Porpoise (Phocoena phocoena) Inhabiting Hokkaido, Japan

Growth and Reproduction in Harbour Porpoise (Phocoena phocoena) Inhabiting Hokkaido, Japan

Temporary Hearing Threshold Shift at Ecologically Relevant Frequencies in a Harbor Porpoise (Phocoena phocoena) Due to Exposure to a Noise Band Centered at 88.4 kHz

Temporary Hearing Threshold Shift at Ecologically Relevant Frequencies in a Harbor Porpoise (Phocoena phocoena) Due to Exposure to a Noise Band Centered at 88.4 kHz

Temporary Threshold Shift in a Second Harbor Porpoise (Phocoena phocoena) After Exposure to a One-Sixth-Octave Noise Band at 1.5 kHz and a 6.5 kHz Continuous Wave

Temporary Threshold Shift in a Second Harbor Porpoise (Phocoena phocoena) After Exposure to a One-Sixth-Octave Noise Band at 1.5 kHz and a 6.5 kHz Continuous Wave

Temporary Hearing Threshold Shift in Harbor Porpoises (Phocoena phocoena) Due to One-Sixth-Octave Noise Bands at 63 kHz

Temporary Hearing Threshold Shift in Harbor Porpoises (Phocoena phocoena) Due to One-Sixth-Octave Noise Bands at 63 kHz

Effect of a Bubble Screen on the Behavioral Responses of Captive Harbor Porpoises (Phocoena phocoena) Exposed to Airgun Sounds

Effect of a Bubble Screen on the Behavioral Responses of Captive Harbor Porpoises (Phocoena phocoena) Exposed to Airgun Sounds

Behavioral Responses of a Harbor Porpoise (Phocoena phocoena) to a Series of Four Different Simulated Low-Frequency Sonar Sounds (1.33-1.43 kHz)

Behavioral Responses of a Harbor Porpoise (Phocoena phocoena) to a Series of Four Different Simulated Low-Frequency Sonar Sounds (1.33-1.43 kHz)

Clinical, pathological, and laboratory diagnoses of diseases of harbour porpoises (Phocoena phocoena), live stranded on the Dutch and adjacent coasts from 2003 to 2016

Harbour porpoises (Phocoena phocoena) in the North Sea live in an environment heavily impacted by humans, the consequences of which are a concern for their health. Autopsies carried out on stranded harbour porpoises provide an opportunity to assess health problems in this species. We performed 61 autopsies on live-stranded harbour porpoises, which died following admission to a rehabilitation centre between 2003 and 2016. The animals had stranded on the Dutch (n = 52) and adjacent coasts of Belgium (n = 2) and Germany (n = 7). We assigned probable causes for stranding based on clinical and pathological criteria. Cause of stranding was associated in the majority of cases with pathologies in multiple organs (n = 29) compared to animals with pathologies in a single organ (n = 18). Our results show that the three most probable causes of stranding were pneumonia (n = 35), separation of calves from their mother (n = 10), and aspergillosis (n = 9). Pneumonia as a consequence of pulmonary nematode infection occurred in 19 animals. Pneumonia was significantly associated with infection with Pseudalius inflexus, Halocercus sp., and Torynurus convolutus but not with Stenurus minor infection. Half of the bacterial pneumonias (6/12) could not be associated with nematode infection. Conclusions from this study are that aspergillosis is an important probable cause for stranding, while parasitic infection is not a necessary prerequisite for bacterial pneumonia, and approximately half of the animals (29/61) probably stranded due to multiple causes. An important implication of the observed high prevalence of aspergillosis is that these harbour porpoises suffered from reduced immunocompetence.

Temporary Hearing Threshold Shift in Harbor Porpoises (Phocoena phocoena) Due to One-Sixth-Octave Noise Band at 32 kHz

Temporary hearing threshold shift (TTS) caused by fatiguing sounds in the 1.5 to 16 kHz range has been documented in harbor porpoises (Phocoena phocoena). To assess impacts of anthropogenic noise on porpoise hearing, TTS needs to be investigated for other frequencies, as susceptibility appears to depend on the frequency of the fatiguing sound. TTS was quantified after two porpoises (Porpoises F05 and M06) were exposed for 1 hour to a continuous one-sixth-octave noise band centered at 32 kHz, at average received sound pressure levels of 118 to 148 dB re 1 µPa, and at a sound exposure level (SEL) range of 154 to 184 dB re 1 µPa2s. Hearing thresholds for 32, 44.8, and 63 kHz tonal signals were determined before and after exposure to quantify initial TTS and recovery. Porpoise M06’s hearing was tested 1 to 4 min after exposure. At 32 kHz, the lowest SEL that resulted in significant TTS1-4 (3.4 dB) was 166 dB re 1 µPa2s. At 44.8 kHz, the lowest SEL that resulted in significant TTS1-4 (5.2 dB) was 178 dB re 1 µPa2s. The highest TTS1-4 (18.3 dB) occurred at 44.8 kHz after exposure to 184 dB SEL. Porpoise F05’s hearing was tested 12 to 16 min after exposure. At 32 kHz, the lowest SEL that resulted in significant TTS12-16 (3.5 dB) was 184 dB re 1 µPa2s. At 44.8 kHz, the lowest SEL that resulted in significant TTS12-16 (1.2 dB) was 178 dB re 1 µPa2s. The highest TTS12-16 (8.2 dB) occurred in Porpoise F05 at 44.8 kHz after exposure to 184 dB SEL. At 63 kHz, no TTS could be elicited in either animal. Considering that Porpoise F05 had more time than Porpoise M06 for recovery, the susceptibility of the two porpoises to TTS after exposure to sounds of 32 kHz was similar. In the range investigated so far (1.5 to 32 kHz), susceptibility to TTS appears to increase with increasing frequency below ~6.5 kHz, and to decrease with increasing frequency above ~6.5 kHz.

Behavioral Responses of Harbor Porpoises (Phocoena phocoena) to U.S. Navy 53C Sonar Signals in Noise

Behavioral Responses of Harbor Porpoises (Phocoena phocoena) to U.S. Navy 53C Sonar Signals in Noise

Temporary Hearing Threshold Shift in Harbor Porpoises (Phocoena phocoena) Due to One-Sixth Octave Noise Band at 16 kHz

Temporary Hearing Threshold Shift in Harbor Porpoises (Phocoena phocoena) Due to One-Sixth Octave Noise Band at 16 kHz

Supplemental Material for Testes Size, Vaginal Complexity, and Behavior in Toothed Whales (Odontocetes): Arms Race or Tradeoff Model for Dusky Dolphins (Lagenorhynchus obscurus), Harbor Porpoises (Phocoena phocoena), and Bottlenose Dolphins (Tursiops spp.)?

Supplemental Material for Testes Size, Vaginal Complexity, and Behavior in Toothed Whales (Odontocetes): Arms Race or Tradeoff Model for Dusky Dolphins (Lagenorhynchus obscurus), Harbor Porpoises (Phocoena phocoena), and Bottlenose Dolphins (Tursiops spp.)?

Behavioral Responses of Harbor Porpoises (Phocoena phocoena) to Sonar Playback Sequences of Sweeps and Tones (3.5-4.1 kHz)

Behavioral Responses of Harbor Porpoises (Phocoena phocoena) to Sonar Playback Sequences of Sweeps and Tones (3.5-4.1 kHz)

Erratum: Assessing the Impact of Underwater Clearance of Unexploded Ordnance on Harbour Porpoises (Phocoena phocoena) in the Southern North Sea

Erratum: Assessing the Impact of Underwater Clearance of Unexploded Ordnance on Harbour Porpoises (Phocoena phocoena) in the Southern North Sea

Swimming Speed of a Harbor Porpoise (Phocoena phocoena) During Playbacks of Offshore Pile Driving Sounds

Swimming Speed of a Harbor Porpoise (Phocoena phocoena) During Playbacks of Offshore Pile Driving Sounds

Growth and Reproductive Activity of a Captive Female Harbour Porpoise (Phocoena phocoena) from Japanese Water

This report describes growth and annual reproductive cycle of female harbour porpoise (Phocoena phocoena) rescued from Japanese water in 2007. The maximum body length was 179 cm and body weight was 69.8 kg. The average daily food consumption was 7.0 kg (ranging 3.7 - 9.9 kg), 11.8% of the body weight. In this report, the porpoise was kept in 17 °C water annually and the blubber thicknesses showed almost constant throughout the year (average 18 mm, range 13 - 22 mm). Therefore, we added new evidence to this hypothesis by showing that body weight and the blubber thickness do not fluctuate seasonally in fixed water temperature. Serum progesterone level of the female showed five peaks from September to November, and each cycle lasted the average of 20.5 days. Such result indicates that harbour porpoise exhibits seasonal polyestrous activity.

Behavioral Responses of a Harbor Porpoise (Phocoena phocoena) to 25.5- to 24.5-kHz Sonar Down-Sweeps With and Without Side Bands

Behavioral Responses of a Harbor Porpoise (Phocoena phocoena) to 25.5- to 24.5-kHz Sonar Down-Sweeps With and Without Side Bands

Short Note: A Record of Twin Fetuses in a Harbor Porpoise (Phocoena phocoena) Stranded on the Dutch Coast

Short Note: A Record of Twin Fetuses in a Harbor Porpoise (Phocoena phocoena) Stranded on the Dutch Coast