The Norway lobster,Nephrops norvegicus,is one of the main commercial crustacean fisheries in Europe.The abundance of Nephrops norvegicus stocks is assessed based on identifying and counting the burrows where they live...The Norway lobster,Nephrops norvegicus,is one of the main commercial crustacean fisheries in Europe.The abundance of Nephrops norvegicus stocks is assessed based on identifying and counting the burrows where they live from underwater videos collected by camera systems mounted on sledges.The Spanish Oceanographic Institute(IEO)andMarine Institute Ireland(MIIreland)conducts annual underwater television surveys(UWTV)to estimate the total abundance of Nephrops within the specified area,with a coefficient of variation(CV)or relative standard error of less than 20%.Currently,the identification and counting of the Nephrops burrows are carried out manually by the marine experts.This is quite a time-consuming job.As a solution,we propose an automated system based on deep neural networks that automatically detects and counts the Nephrops burrows in video footage with high precision.The proposed system introduces a deep-learning-based automated way to identify and classify the Nephrops burrows.This research work uses the current state-of-the-art Faster RCNN models Inceptionv2 and MobileNetv2 for object detection and classification.We conduct experiments on two data sets,namely,the Smalls Nephrops survey(FU 22)and Cadiz Nephrops survey(FU 30),collected by Marine Institute Ireland and Spanish Oceanographic Institute,respectively.From the results,we observe that the Inception model achieved a higher precision and recall rate than theMobileNetmodel.The best mean Average Precision(mAP)recorded by the Inception model is 81.61%compared to MobileNet,which achieves the best mAP of 75.12%.展开更多
Successful commercial aquaculture of crustacean species is dependent on satisfying their nutritional requirements and on producing rapidly growing and healthy animals.The results of the present study provide valuable ...Successful commercial aquaculture of crustacean species is dependent on satisfying their nutritional requirements and on producing rapidly growing and healthy animals.The results of the present study provide valuable information for feeding habits and growth of Nephrops norvegicus L.,1758)under laboratory conditions.The aim of the present study was to examine food consumption,growth and physiology of the Norway lobster N.norvegicus under laboratory conditions.N.norvegicus(15 g wet weight)were distributed into 100l tanks consisting of five numbered compartments each.They were fed the experimental diets(frozen mussels and pellets)for a period of 6 months.A group of starved Nephrops was stocked and fasted for 8 months.Although Nephrops grew well when fed the frozen mussels diet,feeding on a dry pellet feed was unsatisfactory.The starvation group,despite the fact that showed the highest mortality(50%),exhibited a remarkable tolerance to the lack of food supply.The study offers further insight by correlating the amino acid profiles of Nephrops tail muscle with the two diets.The deviations from the mussel’s diet for asparagine,alanine and glutamic acid suggest a deficiency of these amino acids in this diet.The results of the present study showed that the concentrations of free amino acids are lower in relative amount than those of protein-bound amino acids,except for arginine,proline and glycine.The present study contributes to the improvement of our knowledge on nutritional requirements of the above species.展开更多
基金Open Access Article Processing Charges has been funded by University of Malaga.
文摘The Norway lobster,Nephrops norvegicus,is one of the main commercial crustacean fisheries in Europe.The abundance of Nephrops norvegicus stocks is assessed based on identifying and counting the burrows where they live from underwater videos collected by camera systems mounted on sledges.The Spanish Oceanographic Institute(IEO)andMarine Institute Ireland(MIIreland)conducts annual underwater television surveys(UWTV)to estimate the total abundance of Nephrops within the specified area,with a coefficient of variation(CV)or relative standard error of less than 20%.Currently,the identification and counting of the Nephrops burrows are carried out manually by the marine experts.This is quite a time-consuming job.As a solution,we propose an automated system based on deep neural networks that automatically detects and counts the Nephrops burrows in video footage with high precision.The proposed system introduces a deep-learning-based automated way to identify and classify the Nephrops burrows.This research work uses the current state-of-the-art Faster RCNN models Inceptionv2 and MobileNetv2 for object detection and classification.We conduct experiments on two data sets,namely,the Smalls Nephrops survey(FU 22)and Cadiz Nephrops survey(FU 30),collected by Marine Institute Ireland and Spanish Oceanographic Institute,respectively.From the results,we observe that the Inception model achieved a higher precision and recall rate than theMobileNetmodel.The best mean Average Precision(mAP)recorded by the Inception model is 81.61%compared to MobileNet,which achieves the best mAP of 75.12%.
文摘Successful commercial aquaculture of crustacean species is dependent on satisfying their nutritional requirements and on producing rapidly growing and healthy animals.The results of the present study provide valuable information for feeding habits and growth of Nephrops norvegicus L.,1758)under laboratory conditions.The aim of the present study was to examine food consumption,growth and physiology of the Norway lobster N.norvegicus under laboratory conditions.N.norvegicus(15 g wet weight)were distributed into 100l tanks consisting of five numbered compartments each.They were fed the experimental diets(frozen mussels and pellets)for a period of 6 months.A group of starved Nephrops was stocked and fasted for 8 months.Although Nephrops grew well when fed the frozen mussels diet,feeding on a dry pellet feed was unsatisfactory.The starvation group,despite the fact that showed the highest mortality(50%),exhibited a remarkable tolerance to the lack of food supply.The study offers further insight by correlating the amino acid profiles of Nephrops tail muscle with the two diets.The deviations from the mussel’s diet for asparagine,alanine and glutamic acid suggest a deficiency of these amino acids in this diet.The results of the present study showed that the concentrations of free amino acids are lower in relative amount than those of protein-bound amino acids,except for arginine,proline and glycine.The present study contributes to the improvement of our knowledge on nutritional requirements of the above species.
