Halogenated natural products(HNPs)are considered to be emerging contaminants whose environmental distribution and fate are only incompletely known.Therefore,several persistent and bioaccumulative HNP groups,together w...Halogenated natural products(HNPs)are considered to be emerging contaminants whose environmental distribution and fate are only incompletely known.Therefore,several persistent and bioaccumulative HNP groups,together with manmade polychlorinated biphenyls(PCBs)and polybrominated diphenyl ethers(PBDEs),were quantified in the blubber of nine sperm whales(Physeter macrocephalus)stranded on the coast of the Mediterranean Sea in Italy.The naturally occurring polybrominated hexahydroxanthene derivatives(PBHDs;sum of TetraBHD and TriBHD)were the most prominent substance class with up to 77,000 ng/g blubber.The mean PBHD content(35,800 ng/g blubber)even exceeded the one of PCBs(28,400 ng/g blubber),although the region is known to be highly contaminated with manmade contaminants.Based on mean values,Q1∼PBDEs>MeO-BDEs∼2,2′-diMeO-BB 80 and several other HNPs followed with decreasing amounts.All blubber samples contained an abundant compound whose molecular formula(C_(16)H_(19)Br_(3)O_(2))was verified using high-resolution mass spectrometry.The only plausible matching isomer was(2S,4′S,9R,9′S)-2,7-dibromo-4′-bromomethyl-1,1-dimethyl-2,3,4,4′,9,9′-9,9′-hexahydro-1H-xanthen-9-ol(OH-TriBHD),a hydroxylated secondary metabolite previously detected together with TriBHD and TetraBHD in a sponge known to be a natural producer of PBHDs.The estimated mean amount of the presumed OH-TriBHD was 3000 ng/g blubber,which is unexpectedly high for hydroxylated compounds in the lipids of marine mammals.展开更多
Spatiotemporal information is crucial for cetacean research and conservation,particularly for wide-ranging and migratory species.Sperm whales(Physeter macrocephalus)are distributed worldwide in deep oceans;however,lit...Spatiotemporal information is crucial for cetacean research and conservation,particularly for wide-ranging and migratory species.Sperm whales(Physeter macrocephalus)are distributed worldwide in deep oceans;however,little is known about the species in the western margin of the Pacific Ocean.Here,we examined the available information related to the occurrence,distribution,and potential habitats of sperm whales in the waters off China.Historical whaling information(18th–20th century)indicates that sperm whales have been captured in the East China Sea(ECS)and South China Sea(SCS).Furthermore,sporadic strandings have been recorded since the 1910s,and more frequently from 1990 onwards.Since 1990,accidental sightings have been documented in the eastern ECS,northeastern and southern SCS,and their adjacent waters.More recently(2019–2022),field encounters have been reported in dedicated ship-based investigations in the Xisha and Nansha waters,providing robust evidence of the regular existence and potential residency of sperm whales in the northwestern and central areas of the SCS.Female nursery groups suggest that the Xisha waters might be an important nursing ground for sperm whales.Satellite tracking data from four adults showed that sperm whales in the SCS might display both fine-scale and long-distance movements.Taken together,it appears that sperm whales are currently active in the waters off China,and that deep waters(depth>200 m)in the ECS and SCS may provide the species with critical habitats.This review provides crucial baseline information on sperm whales in the waters off China,which may help to facilitate future research efforts and conservation initiatives for the species at national and cross-regional scales.More field investigations and other monitoring approaches including acoustic monitoring,biologging,photo-identification,and genetics are required to reveal the distribution,movement,and habitat use patterns of sperm whales in these waters.展开更多
Information on the gut microbiome composition of different mammals could provide novel insights into the evolution of mammals and succession of microbial communities in different hosts.However,there is limited informa...Information on the gut microbiome composition of different mammals could provide novel insights into the evolution of mammals and succession of microbial communities in different hosts.However,there is limited information on the gut microbiome composition of marine mammals,especially cetaceans because of sampling constraints.In this study,we investigated the diversity and composition of microbial communities in the stomach,midgut,and hindgut of 2 stranded short-finned pilot whales(Globicephala macrorhynchus)and hindgut of a stranded pygmy sperm whale(Kogia breviceps)by using 16S rRNA gene amplicon sequencing technology.On the basis of the 50 most abundant operational taxonomic units,principal coordinate analysis,and non-metric multidimensional scaling analysis,we confirmed that the gut microbial communities of the 3 whales were different.Our results revealed that the gut microbiome of 1 stranded short-finned pilot whale GM16 was dominated by Firmicutes(mainly Clostridium)and Fusobacteria;whereas that of the other pilot whale GM19 was composed of Gammaproteobacteria and Bacteroidetes(mainly Vibrio and Bacteroides,respectively),probably caused by intestinal disease and antibiotic treatment.The gut microbiome of the pygmy sperm whale was dominated by Firmicutes and Bacteroidetes.Moreover,different gastrointestinal tract regions harbored different microbial community structures.To our knowledge,this is the first report of the gut microbiome of short-finned pilot whales,and our findings will expand our current knowledge on microbial diversity and composition in the gastrointestinal tract of cetaceans.展开更多
文摘Halogenated natural products(HNPs)are considered to be emerging contaminants whose environmental distribution and fate are only incompletely known.Therefore,several persistent and bioaccumulative HNP groups,together with manmade polychlorinated biphenyls(PCBs)and polybrominated diphenyl ethers(PBDEs),were quantified in the blubber of nine sperm whales(Physeter macrocephalus)stranded on the coast of the Mediterranean Sea in Italy.The naturally occurring polybrominated hexahydroxanthene derivatives(PBHDs;sum of TetraBHD and TriBHD)were the most prominent substance class with up to 77,000 ng/g blubber.The mean PBHD content(35,800 ng/g blubber)even exceeded the one of PCBs(28,400 ng/g blubber),although the region is known to be highly contaminated with manmade contaminants.Based on mean values,Q1∼PBDEs>MeO-BDEs∼2,2′-diMeO-BB 80 and several other HNPs followed with decreasing amounts.All blubber samples contained an abundant compound whose molecular formula(C_(16)H_(19)Br_(3)O_(2))was verified using high-resolution mass spectrometry.The only plausible matching isomer was(2S,4′S,9R,9′S)-2,7-dibromo-4′-bromomethyl-1,1-dimethyl-2,3,4,4′,9,9′-9,9′-hexahydro-1H-xanthen-9-ol(OH-TriBHD),a hydroxylated secondary metabolite previously detected together with TriBHD and TetraBHD in a sponge known to be a natural producer of PBHDs.The estimated mean amount of the presumed OH-TriBHD was 3000 ng/g blubber,which is unexpectedly high for hydroxylated compounds in the lipids of marine mammals.
基金This research was financially supported by the National Natural Science Foundation of China(Grant Nos.42225604 and 41422604)the“One Belt and One Road”Science and Technology Cooperation Special Program of the International Partnership Program of the Chinese Academy of Sciences(Grant No.183446KYSB20200016)+2 种基金the Key Deployment Project of the Center for Ocean Mega-Science of the Chinese Academy of Sciences(Grant No.COMS 2020Q15)the Zhilan Foundation(Grant No.2022010291B)the Small Grant in Aid of Research from the Society for Marine Mammalogy.
文摘Spatiotemporal information is crucial for cetacean research and conservation,particularly for wide-ranging and migratory species.Sperm whales(Physeter macrocephalus)are distributed worldwide in deep oceans;however,little is known about the species in the western margin of the Pacific Ocean.Here,we examined the available information related to the occurrence,distribution,and potential habitats of sperm whales in the waters off China.Historical whaling information(18th–20th century)indicates that sperm whales have been captured in the East China Sea(ECS)and South China Sea(SCS).Furthermore,sporadic strandings have been recorded since the 1910s,and more frequently from 1990 onwards.Since 1990,accidental sightings have been documented in the eastern ECS,northeastern and southern SCS,and their adjacent waters.More recently(2019–2022),field encounters have been reported in dedicated ship-based investigations in the Xisha and Nansha waters,providing robust evidence of the regular existence and potential residency of sperm whales in the northwestern and central areas of the SCS.Female nursery groups suggest that the Xisha waters might be an important nursing ground for sperm whales.Satellite tracking data from four adults showed that sperm whales in the SCS might display both fine-scale and long-distance movements.Taken together,it appears that sperm whales are currently active in the waters off China,and that deep waters(depth>200 m)in the ECS and SCS may provide the species with critical habitats.This review provides crucial baseline information on sperm whales in the waters off China,which may help to facilitate future research efforts and conservation initiatives for the species at national and cross-regional scales.More field investigations and other monitoring approaches including acoustic monitoring,biologging,photo-identification,and genetics are required to reveal the distribution,movement,and habitat use patterns of sperm whales in these waters.
基金This study was supported by grants from the National Key R&D Program of China(Grant numbers 2017YFC0306702 and 2016YFC0300803)National Natural Science Foundation of China(Grant No.41506139)Youth Innovation Promotion Association of Chinese Academy of Sciences.This study was performed under Ethical Statement number IDSSE-SYLL-MMMBL-01.
文摘Information on the gut microbiome composition of different mammals could provide novel insights into the evolution of mammals and succession of microbial communities in different hosts.However,there is limited information on the gut microbiome composition of marine mammals,especially cetaceans because of sampling constraints.In this study,we investigated the diversity and composition of microbial communities in the stomach,midgut,and hindgut of 2 stranded short-finned pilot whales(Globicephala macrorhynchus)and hindgut of a stranded pygmy sperm whale(Kogia breviceps)by using 16S rRNA gene amplicon sequencing technology.On the basis of the 50 most abundant operational taxonomic units,principal coordinate analysis,and non-metric multidimensional scaling analysis,we confirmed that the gut microbial communities of the 3 whales were different.Our results revealed that the gut microbiome of 1 stranded short-finned pilot whale GM16 was dominated by Firmicutes(mainly Clostridium)and Fusobacteria;whereas that of the other pilot whale GM19 was composed of Gammaproteobacteria and Bacteroidetes(mainly Vibrio and Bacteroides,respectively),probably caused by intestinal disease and antibiotic treatment.The gut microbiome of the pygmy sperm whale was dominated by Firmicutes and Bacteroidetes.Moreover,different gastrointestinal tract regions harbored different microbial community structures.To our knowledge,this is the first report of the gut microbiome of short-finned pilot whales,and our findings will expand our current knowledge on microbial diversity and composition in the gastrointestinal tract of cetaceans.
