Nature Conservation Research

17–31

Authors: Setyawan E., Sianipar A.B., Erdmann M.V., Fischer A.M., Haddy J.A., Beale C.S., Lewis S.A., Mambrasar R.

Though extremely valuable to the local marine tourism industry, there is a dearth of published information on the ecology and population dynamics of reef manta rays (Mobula alfredi) in Raja Ampat, West Papua, Indonesia. Knowledge of the movement ecology in particular of this large and scattered population is urgently needed to better manage the rapidly expanding manta-focused tourism. Here we report the results of an initial passive acoustic telemetry study designed to provide local managers with the first detailed knowledge of the site use and movement patterns of reef mantas in northern Raja Ampat. A total of 39 reef mantas were tagged with Vemco V16 acoustic transmitters over a 15-month period between 27 November 2013 and 22 February 2015. To monitor their movements, VR2W acoustic receivers were deployed at eight sites corresponding to known manta cleaning and feeding aggregation sites, with receivers downloaded every six months over a two-year initial monitoring period. The duration between tag deployments and last date of detections at sites ranged from 1 to 682 days (mean ± SE = 237 ± 27). The cumulative number of days of manta detections at receiver sites by individual mantas ranged from 1 to 188 days (mean ± SE = 42 ± 7). Manta Ridge was the most visited site with 565 days of detections. The tagged mantas demonstrated strong site fidelity to the observed aggregation sites. At the same time, they also exhibited seasonal movements within an approximately 150 km long corridor between sites in the Dampier Strait and the northwest of Waigeo Island. Data analysed from a nearby array of six VR2W receivers in southern Raja Ampat (approximately 180 km to the south of the study area) confirmed that none of the tagged mantas were detected in this array, providing further evidence of strong site fidelity and limited movements within northern Raja Ampat. More than 96% of detections occurred during the daytime. The number of detections reached a peak around noon at Yefnabi Kecil and Eagle Rock and slightly earlier at Manta Ridge. These findings have been shared with the Raja Ampat Marine Protected Area Management Authority and are now being used in the formulation of a management plan for this vulnerable and economically important species to ensure the long-term health of Raja Ampat's reef mantas and the sustainability of manta tourism in the region.

44–58

Authors: Mamaev E.G.

The Kuril Seal Phoca vitulina ssp. stejnegeri is a permanent inhabitant of the coast of the Commander Islands. The ecology of the Kuril Seal, and in particular, the features of its life cycle, the population structure and the level of fertility are poorly known. Most publications are devoted to the study of populations and spatial distribution of this animal on the islands. From June to October 2017, the current occurrence, features of spatial distribution, reproductive success of Phoca vitulina ssp. stejnegeri, seasonal dynamics of the number and the comparison of the accuracy of various methods of its counting have been carried out on Bering Island, Toporkov Island, Ariy Kamen Island, and at a site Bobroviye Kamni on Medniy Island. The material on the number and spatial distribution of the seals was collected using an unmanned aerial vehicle, quadrocopter (drone). In this study, the Kuril Seal was first counted on the islands by aerophotography. The determination of the population size has been carried out during the active reproduction phase of the Kuril Seal– from mid-June to 10th July 2017. Our study showed that the accounted abundance of the Kuril Seal was 1543 individuals, including 343 pups on Bering Island and Toporkov Island. The abundance of Phoca vitulina ssp. stejnegeri on Medniy Island has been counted using the extrapolation method. It was estimated at 689 individuals. And the total number of this animal on the Commander Islands was 3344 individuals. For the first time, we obtained data on the proportion of pups (22.2%) of the Kuril Seal on the Commander Islands in rookeries during the breeding season and the specific birth rate (17.4%) was calculated. Up to 69.3% of the total number of Kuril Seals is present in large rookeries and only a small portion is presented by small groups or individuals. The proportion of pups born in large rookeries is 72%. We found an increase of the Phoca vitulina ssp. stejnegeri abundance in the rookeries during the moult period (August). The abundance of individuals continued to grow in some rookeries in September. A comparison of the accuracy of the visual, traditional on the Commander Islands, method of animal counting with data obtained using the aerophotography method showed that in the case of counting from the boat, an observer can register an average of 67.7% of adult individuals and 24% of pups. In case of observation from the first seaside terrace of a shore, the observer can see 39.6% of individuals (adults and pups). And in case of observation from the slopes (height of 17 m and higher) the observer can see up to 62% of individuals (adults and pups). To discuss the long-term dynamics of the number of Kuril Seals on the Commander Islands it is required to conduct a detailed analysis of all available data, as they were collected by using different methods, which are not correctly comparable with the newly obtained results.

68–72

Authors: Zaytsev A.A., Stepanov S.Yu., Makarevich P.R., Ishkulov D.G., Troshichev A.R., Litvinov Yu.V., Mosalov V.A., Skarednov S.Yu., Galchansky V.A.

The most important stage of keeping seals in captivity conditions is training of pups which have finished breastfeeding to feed on solid food (fattening). On expedition in 2016 the Murmansk Marine Biological Institute (MMBI) staff captured five pups of the Atlantic gray seal (Halichoerus grypus grypus) for the purpose of carrying out experimental studies. The caught animals were transported to the MMBI aqua complex in Gadzhievo. Three of the five captured animals began to feed on thawed fish without additional measures. A forced battening method was successfully applied for the two remaining animals. Additions made to the original technique of forced battening have proved its efficiency.

78–81

Authors: Pinheiro F.C.F., Pinheiro H.T., Costa T.J.F., Teixeira J.B., Gasparini J., Joyeux J.-C., Martins A.S.

The harvesting of marine organisms for aquarium and ornamental art crafts is a very common and widespread activity, threatening a number of coral reef species. The goal of this manuscript is to report the intensive harvesting of two marine invertebrate species, the starfish Oreaster reticulatus and the gorgonian Phyllogorgia dilatata, in reef environments of a national priority area for the creation of a Marine Protected Area (MPA) in the Espírito Santo State, central coast of Brazil. These species were present on the 2003 Brazilian Red List of Endangered species as threatened of extinction, but P. dilatata was removed from the most recent 2014 Brazilian Red List, while O. reticulatus is currently considered vulnerable. Neither species have been assessed by IUCN. The harvest of these invertebrates was registered in 17% of the 51 days of monitoring (ten expeditions between March 2005 and February 2006), with catches of up to 24 starfishes and 1000 gorgonians in a single day. Starfishes used to be sold to local traders for US$ 0.50 each, and each gorgonian for US$ 0.15. This starfish is already in decline on a regional scale, and the actual harvesting rate of the gorgonian could lead to the extinction of the local population in about 17 years of exploitation. Due to the ecological importance of these two endangered species, their harvest threatens the entire local rocky reef ecosystem. Further ecological and fisheries studies on these species should be conducted, and the definition and creation of the MPA could help to manage all the unsustainable activities conducted and expected in the region.

88–90

Authors: Zaytsev A.A., Yakovlev A.P., Pakhomov M.V.

Lagenorhynchus albirostris is one of the most common Cetacean species in the Barents Sea. However, there is not a mention of its appearance in the Kola Bay. The present report confirms the appearance of a group of Lagenorhynchus albirostris in the Kola Bay near the aquacomplex of the Murmansk Marine Biological Institute of the Kola Research Centre of RAS, Polyarny town, in autumn 2011.