Sound production of the critically endangered totoaba (Totoaba macdonaldi): Laying the foundation for conservation of this species through passive acoustic monitoring

Effective management of wild animal populations relies on an understanding of their spatio-temporal distributions. Passive acoustic monitoring (PAM) is a non-invasive method to investigate the distribution of free-ranging species that reliably produce sound. Critically endangered Antarctic blue whales (Balaenoptera musculus intermedia) (ABWs) co-occur with pygmy blue whales (B. m. brevicauda) (PBWs) around New Zealand. Nationally, both are listed as “data deficient” due to difficulties in access and visual sub-species identification. PAM was used to investigate the distributions of blue whales via sub-species specific song detections in central New Zealand. Propagation models, incorporating ambient noise data, enabled the comparison of detections among recording locations in different marine environments. ABW detections peaked during austral winter and spring, indicating that New Zealand, and the South Taranaki Bight (STB) in particular, is a migratory corridor for ABWs. Some ABW calls were also detected during the breeding season (September and October). PBW calls were highly concentrated in the STB, particularly between March and May, suggesting that an aggregation of PBWs may occur here. Therefore, the STB is of great importance for both sub-species of blue whale. PBW detections were absent from the STB during parts of austral spring, but PBWs were detected at east coast locations during this time. Detection area models were valuable when interpreting and comparing detections among recording locations. The results provide sub-species specific information required for management of critically endangered ABWs and highlight the relative importance of central New Zealand for both sub-species of blue whale.

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Sound production by the Shi drum Umbrina cirrosa and comparison with the brown meagre Sciaena umbra : a passive acoustic monitoring perspective

Journal of Fish Biology ◽

10.1111/jfb.12926 ◽

2016 ◽

Vol 88 (4) ◽

pp. 1655-1660 ◽

Cited By ~ 6

Author(s):

M. Picciulin ◽

M. Bolgan ◽

A. B. Corò ◽

G. Calcagno ◽

S. Malavasi

Keyword(s):

Sound Production ◽

Acoustic Monitoring ◽

Passive Acoustic Monitoring ◽

Passive Acoustic

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Last call: Passive acoustic monitoring shows continued rapid decline of critically endangered vaquita

The Journal of the Acoustical Society of America ◽

10.1121/1.5011673 ◽

2017 ◽

Vol 142 (5) ◽

pp. EL512-EL517 ◽

Cited By ~ 17

Author(s):

Len Thomas ◽

Armando Jaramillo-Legorreta ◽

Gustavo Cardenas-Hinojosa ◽

Edwyna Nieto-Garcia ◽

Lorenzo Rojas-Bracho ◽

...

Keyword(s):

Acoustic Monitoring ◽

Critically Endangered ◽

Rapid Decline ◽

Passive Acoustic Monitoring ◽

Passive Acoustic

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Estimating the abundance of the critically endangered Baltic Proper harbour porpoise (Phocoena phocoena) population using passive acoustic monitoring

10.22541/au.162755770.03327482/v1 ◽

2021 ◽

Author(s):

Mats Amundin ◽

Julia Carlström ◽

Len Thomas ◽

Ida Carlén ◽

Jens Koblitz ◽

...

Keyword(s):

Baltic Sea ◽

Acoustic Monitoring ◽

Harbour Porpoise ◽

Critically Endangered ◽

Phocoena Phocoena ◽

Passive Acoustic Monitoring ◽

Animal Populations ◽

Baltic Proper ◽

The Baltic ◽

Passive Acoustic

Knowing the abundance of a population is a crucial component to assess its conservation status and develop effective conservation plans. For most cetaceans, abundance estimation is difficult given their cryptic and mobile nature, especially when the population is small and has a transnational distribution. In the Baltic Sea, the number of harbour porpoises (Phocoena phocoena) has collapsed since the mid-20th century and the Baltic Proper harbour porpoise is listed as Critically Endangered by the IUCN; however, its abundance remains unknown. Here, one of the largest ever passive acoustic monitoring studies was carried out by eight Baltic Sea nations to estimate the abundance of the Baltic Proper harbour porpoise for the first time. By logging porpoise echolocation signals at 298 stations during May 2011-April 2013, calibrating the loggers’ spatial detection performance at sea, and measuring the click rate of tagged individuals, we estimated an abundance of 66-1,143 individuals (95% CI, point estimate 490) during May-October within the population’s proposed management border. The small abundance estimate strongly supports that the Baltic Proper harbour porpoise is facing an extremely high risk of extinction, and highlights the need for immediate and efficient conservation actions through international cooperation. It also provides a starting point in monitoring the trend of the population abundance to evaluate the effectiveness of management measures and determine its interactions with the larger neighbouring Belt Sea population. Further, we offer evidence that design-based passive acoustic monitoring can generate reliable estimates of the abundance of rare and cryptic animal populations across large spatial scales.

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