Home /Search
Search datasets
We have found 32 datasets for the keyword "homarus americanus". You can continue exploring the search results in the list below.
Datasets: 105,253
Contributors: 42
Results
32 Datasets, Page 1 of 4
American lobster (Homarus americanus) abundance and biological characteristics collected from SCUBA dive surveys in the Bay of Fundy from 1982-2021
This dataset reports on lobster abundance and individual biological characteristics (size, sex, shell hardness, egg status), along with seabed substrate information, collected at various coastal sites in the Bay of Fundy, Canada. Surveys were conducted over a 40-year period between 1982 and 2021. Survey areas and SCUBA dive sites were located around Grand Manan Island, Deer Island, Campobello Island, and along the Bay of Fundy’s New Brunswick shore stretching from Passamaquoddy Bay, east to Maces Bay. One survey area was located on the Bay of Fundy’s southern shore (Nova Scotia) in the Annapolis Basin (Lawton et al. 1995). The data represent a compilation of SCUBA diving surveys (1003 belt transects) conducted directly by Fisheries and Oceans Canada (DFO) scientific SCUBA divers (1982-2019), or by contracted commercial divers funded in association with outside collaborating organizations; Department of Fisheries and Agriculture (DFA; 1990 – 1993), the Grand Manan Fishermen’s Association (GMFA; 2013-2015), and the University of New Brunswick (UNB; 2019-2021).Cite this data as: Lawton P, Dinning K, Rochette R, Teed L. American lobster (Homarus americanus) abundance and biological characteristics collected from SCUBA dive surveys in the Bay of Fundy from 1982-2021. Published August 2024. Coastal Ecosystems Science Division, Fisheries and Oceans Canada, St. Andrews, N.B.For additional information please see:Campbell, A. 1990. Aggregations of berried lobsters (Homarus americanus) in shallow waters off Grand Manan, eastern Canada. DFO Can. J. Fish. Aquat. Sci. 47: 520-523.Denton, C.M. 2020. Maritimes Region Inshore Lobster Trawl Survey Technical Description. DFO Can. Tech. Rep. Fish. Aquat. Sci. 3376: v + 52 p.Lawton, P. 1993. Salmon aquaculture and the traditional invertebrate fisheries of the Fundy Isles region: habitat mapping and impact definition: Cooperation Agreement on Fisheries and Aquaculture Development. Submitted by Peter Lawton to the New Brunswick Department of Fisheries and Aquaculture, 84 p. Unpublished monograph. Available from Fisheries and Oceans Canada Library, Dartmouth, NS (Monographs: SH 380.2 .C2 .L39 1992).https://science-catalogue.canada.ca/record=3943769~S6Lawton, P., Robichaud, D.A., and Moisan, M. 1995. Characteristics of the Annapolis Basin, Nova Scotia, lobster fishery in relation to proposed marine aquaculture development. DFO Can. Tech. Rep. Fish. Aquat. Sci. 2035: iii + 26 p.Lawton, P., Robichaud, D.A., Rangeley, R.W., and Strong, M.B. 2001. American Lobster, Homarus americanus, population characteristics in the lower Bay of Fundy (Lobster Fishing Areas 36 and 38) based on fishery independent sampling. DFO Can. Sci. Advis. Sec. Res. Doc. 2001/093.Wentworth, C.K. 1922. A Scale of Grade and Class Terms for Clastic Sediments. The Journal of Geology 30(5): 377-392.Dinning, K.M., Lawton, P., and Rochette, R. 2025. Increased use of mud bottom by juvenile American lobsters (Homarus americanus) in Maces Bay and Seal Cove, Bay of Fundy, after three decades of population increases and predator declines. Canadian Journal of Fisheries & Aquatic Sciences 82; https://doi.org/10.1139/cjfas-2023-0312
Scientific trawl surveys of American lobster (Homarus americanus) and rock crab (Cancer irroratus) in the Magdalene Island
A research survey on American lobster (Homarus americanus) and rock crab (Cancer irroratus) has been carried out annually on the Magdalen Islands since 1995 to assess the abundance and structure of populations in this area. The survey is carried out during the first two weeks of September and covers the southern part of the Magdalen Islands, from "Baie de Plaisance" to "Grande-Entrée", extending slightly eastwards between "Havre-aux-Maisons" and "Grande-Entrée". The survey lasts 8 to 15 days, depending of the weather conditions, and covers a maximum of 48 stations. Approximately half of the stations are surveyed in duplicate (two tows per station). The tows always cover 500 meters, with a slightly variable trawl opening (as explained above), averaging around 10 meters.The gear used is a Nephrops trawl, a benthic trawl originally developed for langoustine fishing in Brittany, but slightly modified to target lobster. The trawl is deployed from the CCGS Leim and the harvested organisms are hauled aboard and sorted. Cephalothorax length, sex and shell stage are recorded for all lobsters. This is supplemented by information on reproductive conditions for certain size classes, and dissections of 25 males and 25 females per mission. Rock crabs are also included in the survey and are counted with additional measurements of shell width, sex and shell condition that are recorded on predetermined stations. For other stations individuals data are collected depending on the time available between trawl hauls.The publication contains 4 files; the "Information_stations" file which contains the data of the stations, the "Data_homard_lobster_survey" file which contains the measurements of each lobster, the "Nombre_crabe_crab_number" file which contains the count of rock crabs, the "Mesure_crabe_crab_measurement" file contains the characteristics measured for each crab. Each of the files can be linked by the "date", "st", "tr" columns. The “bat” column notes the boat code, because the gear is not deployed in the same way on each boat.*This record consist of raw data and quality has not been verifiedAssociated species are identified and semi-quantitatively counted directly on the sorting table, and the results are presented in the following publication: https://open.canada.ca/data/en/dataset/99cb7034-f3d5-4da4-a5bc-e81315cfb8eb
Commercial catches sampling program in the Estuary and Gulf of St. Lawrence – American lobster (Homarus americanus)
SummaryThe Quebec region of the Department of Fisheries and Oceans (DFO) is responsible for the assessment of several fish and invertebrate stocks exploited in the Estuary and the northern Gulf of St. Lawrence. The commercial catches sampling program is one of the sources of information used to complete these assessments. The data collected by this program, at wharf or at sea, offers among other things the advantage of a relatively large spatio-temporal coverage and provides some of the necessary knowledge to assess the demography and the structure of the exploited populations. This program is implemented by specialized DFO staff whose main mandate is to collect biological data on groundfish, pelagic fish and marine invertebrate species that are commercially exploited in the various marine communities.DataThis dataset on the American lobster (Homarus americanus) includes the metadata, sample weight, cephalothorax length, sex and the number of specimens measured. This dataset covers the periods of 1998 and 2000 to present. In order to protect the confidentiality of the sources, some informations (such as those concerning the vessel) have been excluded and others (such as the date of capture) have been simplified. Entries where there was only one vessel in a fishing area for a given year were also excluded. Further information including the fishing areas coordinates can be found by clicking on the «Atlantic and Arctic commercial fisheries» and «Fishing areas» links below.
Habitat associations of juvenile American lobster in three nearshore areas of Newfoundland
This project was completed by the Productive Capacity group (Coastal and Freshwater Ecology Section) in the Newfoundland and Labrador Science Branch of Fisheries and Oceans Canada (DFO). American lobster (Homarus americanus) is a commercially important decapod crustacean species along the east coast of North America, ranging from the Labrador coast south to Cape Hatteras. Juvenile lobster < 40 mm CL (carapace length) recruitment has been studied extensively in the southern portions of their range. However, investigations of settlement habitat association and recruitment of juvenile lobster in the northern extremes along the Newfoundland coast have been largely unsuccessful. We investigated juvenile lobster density, habitat, and depth associations in three areas of Newfoundland, using scuba – Port Saunders area, 8 dives conducted 28 September - 2 October 2017, and Burin Peninsula 10 dives (7 Placentia Bay, 3 Fortune Bay) conducted 30 September - 4 October 2018 over a total seabed area of 9,138 m2, within 200 meters of shore. Port Saunders and Fortune Bay had relatively higher lobster density (0.09 and 0.40 m-2, respectively); >65% were juveniles, in contrast to Placentia Bay where lobster densities of all size groups were low (mean 0.01 m-2) and no juvenile lobsters were observed at all. Where observed all juvenile lobster were significantly associated with shallow (<6 m) habitat and showed no overlap with distribution of adults (>82.5 mm CL) which we observed at depths 6 to 17 m. Our sites were dominated by varying mixes of cobble and pebble (77%); rock/bedrock (12%) and mud/sand/small pebble (11%) substrates interspersed with overlying kelp (32%) and eelgrass (11%) vegetation. We observed no significant associations with substrate or vegetation. This record contains the geographic locations of the 7 Placentia Bay sites surveyed, and information on the timing and type of data collected at each site, which was one component supported by Coastal Environmental Baseline Program of a larger collaborative project.
Biodiversity of the American lobster trawl survey in the Magdalen Islands
A research survey on American lobster (Homarus americanus) has been conducted annually in the Magdalen Islands since 1995 to assess the abundance and structure of lobster populations in this area. Starting in 2007, the main objective was modified to include the diversity and abundance of benthic species associated with lobster habitat. Only benthic species data associated with lobster habitat are presented in this dataset.Surveys were generally conducted during the first two weeks of September from 2007 to 2020 on the entire south side of the Magdalen Islands, from Grosse-Île to Havre-Aubert. The sampling plan consists of 70 trawl tows on 50 fixed stations, between 4 and 35 meters in depth. Some stations had double tows. Specimens were collected using a Nephrops-type door trawl with a total width of 3.04 meters consisting of four Vexar™ lined baskets of 19 millimeter mesh size in order to harvest small individuals. Start and end positions were recorded to calculate the distance traveled at each tow using the geosphere library in R. The year 2011 is not included in the dataset, as biodiversity data were not recorded. Since 2017, the average tow distance has been reduced from 1000 meters to 500 meters. The opening of the trawl is also noted every minute throughout the duration of the tow so that the area sampled can be calculated. The area covered in each tow was the product of the trawl opening and the distance traveled.The two files provided (DarwinCore format) are complementary and are linked by the "eventID" key. The "Event_data" file includes generic activity information, including date and location. The "Occurrence" file includes the taxonomy of the observed species, identified to the species or lowest possible taxonomic level. For abundance and biomass estimates, contact Benoît Bruneau (Benoit.Bruneau@dfo-mpo.gc.ca).For quality controls, all taxonomic names were checked against the World Register of Marine Species (WoRMS) to match recognized standards. The WoRMS match was placed in the "ScientificnameID" field of the occurrence file. Special cases were noted in the "identificationRemarks" field and selected specimens were confirmed with field photos mentioned in "associatedMedia". Data quality checks were performed using the R obistools and WORMS libraries. All sampling locations were spatially validated.
Mountain Goat Inventory Areas for the Mid-Coast Forest District
Inventory Units (Mountain Blocks) for Mountain Goats (Oreamnos americanus) in the Mid Coast portion of the Central Coast/ Port McNeil Forest District
Commercial catches sampling program in the Estuary and Gulf of St. Lawrence
The Quebec region of the Department of Fisheries and Oceans (DFO) is responsible for the assessment of several fish and invertebrate stocks exploited in the Estuary and the northern Gulf of St. Lawrence. The commercial catches sampling program is one of the sources of information used to complete these assessments. The data collected by this program, at wharf or at sea, offers among other things the advantage of a relatively large spatio-temporal coverage and provides some of the necessary knowledge to assess the demography and the structure of the exploited populations. This program is implemented by specialized DFO staff whose main mandate is to collect biological data on groundfish, pelagic fish and marine invertebrate species that are commercially exploited in the various marine communities.The following species have been sampled by this program from 1976 to present:1. American lobster (Homarus americanus)2. American plaice (Hippoglossoides platessoides)3. Atlantic cod (Gadus morhua)4. Atlantic halibut (Hippoglossus hippoglossus)5. Atlantic herring (Clupea harengus)6. Atlantic lyre crab (Hyas araneus)7. Atlantic mackerel (Scomber scombrus)8. Atlantic surfclam (Spisula solidissima)9. Arctic Lyre Crab (Hyas coarctatus)10. Capelin (Mallotus villosus)11. Common softshell clam (Mya arenaria)12. Giant scallop (Placopecten magellanicus)13. Greenland halibut (Reinhardtius hippoglossoides)14. Green urchin (Strongylocentrotus droebachiensis)15. Iceland scallop (Chlamys islandica)16. Redfish (Sebastes sp.)17. Rock crab (Cancer irroratus)18. Sea cucumber (Cucumaria frondosa)19. Snow crab (Chionoecetes opilio)20. Stimpson surfclam (Mactromeris polynyma)21. Waved whelk (Buccinum undatum)22. White hake (Urophycis tenuis)23. Winter flounder (Pseudopleuronectes americanus)24. Yellowtail flounder (Limanda ferruginea)For more information concerning these species, see the «Related Products» section below.
Northumberland Strait Multi-species Trawl Survey Data
PURPOSE:The primary objective of this survey is to obtain an index of the abundance and biomass of American lobster (Homarus americanus) in the Northumberland Strait. This research survey also provides fisheries-independent information for all of the species captured by the trawl.DESCRIPTION:Catch weight, length frequencies, and biological information for crustaceans and fish caught during the annual July-August research vessel trawl survey in Northumberland Strait (NAFO Division 4T). Abundance indices and spatial distribution patterns of commercial and non-commercial crustaceans and other groundfish. PARAMETERS COLLECTED:The full catch is sorted to species, or lowest taxonomic group possible, and weighed. For lobster, carapace length, sex and carapace condition (i.e. stage of moult) are recorded. For female lobster, the presence or absence of eggs is noted and, starting in 2010, the stage of development of the eggs (i.e. new or old) when present was also recorded. Similarly, for crabs, the carapace width, sex and carapace condition (i.e. stage of moult) is recorded as is the presence or absence of eggs (for females). Fish sampling varied over the years but, starting in 2005, length has been recorded for all fish captured.For large catches, the complete catch is sorted and weighed, but sub-sampling, by species, is used for the other measurements.NOTES ON QUALITY CONTROL:Data are checked for irregularities.SAMPLING METHODS:The Northumberland Strait multi-species survey began in 2001 using a stratified random sampling plan. A random selection of sampling sites within the study area is now used. Sampling is completed annually over a 4-week period in July and August. One hundred ten (110) stations are sampled in Northumberland Strait in water depths greater than 4 m at the lowest normal tide. The survey has employed a 286 Rockhopper trawl for all years from 2001 to 2018, except in 2010 and 2011, when a Nephrops trawl was used. In 2019, a new trawl (called the Northumberland trawl) was used in addition to the Rockhopper trawl. The Northumberland trawl is similar to the 286 Rockhopper trawl, but with a smaller footgear and smaller mesh sizes. At each station, the trawl is towed for a set period of time (recently 15 minutes with the rockhopper trawl and 10 minutes with the Northumberland trawl).USE LIMITATION:To ensure scientific integrity and appropriate use of the data, we would encourage you to contact the data custodian.
Southern Gulf of St. Lawrence Ecosystem Research Vessel Survey (September Survey, NAFO Division 4T) Dataset
PURPOSE:The research survey provides a fisheries-independent source of information about all marine living organisms that are captured by the fishing trawl used to obtain samples in the southern Gulf of St. Lawrence.DESCRIPTION:Tow, catch, length frequency, and biological information for fish caught during the annual September research vessel trawl surveys in the southern Gulf of St. Lawrence (NAFO Division 4T). Abundance indices and spatial distribution patterns of commercial and non-commercial groundfish.The catch data that appear in this dataset SHOULD NOT BE USED FOR ECOLOGICAL ANALYSES INVOLVING CATCH RATES. Important factors such as vessel, fishing gear and diurnal periods must be accounted for to use these data in analyses. Please contact the data custodians if you are interested in using this data for any kind of ecological analyses involving catch rates. PARAMETERS COLLECTED:Abundance estimates (ecological); distribution (ecological); species counts (ecological); gear (fishing); vessel information (fishing); point (spatial)NOTES ON QUALITY CONTROL:Scientific names listed in the survey species list have been mapped to recognized standards - marine taxa have been mapped to the World Register of Marine Species (WoRMS) using their online taxon match tool. All sampling locations were plotted on a map to perform a visual check confirming that the latitude and longitude coordinates were within the described sampling area.In 2003, because of a fire aboard the Alfred Needler, the Wilfred Templeman was used for the survey. However, no comparative fishing experiments have been conducted between the Alfred Needler and the Wilfred Templeman. We are therefore unable to integrate the indices derived for 2003 to the remainder of the survey time-series.SAMPLING METHODS:Sampling Method: Consult the "Protocols for research vessel cruises within the Gulf Region (dermersal fish) (1970-1980)" report, link provided in the citations list.USE LIMITATION:To ensure scientific integrity and appropriate use of the data, we would encourage you to contact the data custodian.
SCUBA-Based Assessment of Lobster Density and Structure in the Southern Gulf
PURPOSE:The SCUBA survey was designed to assess the density of small lobsters (1-3 years of age) in rocky reefs, in the nearshore habitat.DESCRIPTION:Total number of transects surveyed and total number of lobsters measured for each site in each year. There are some sites that do not have any coordinates identified, therefore these have not been included in the Web Map Services (WMS). PARAMETERS COLLECTED:Size measurement (biological); species counts (ecological); substrate (geological)SAMPLING METHODS:Transects are laid out from a small vessel using buoys, anchors, and a 100 m leaded rope along the bottom, marked at 5 m intervals. A strip transect survey method is used whereas two divers sample a 1 or 2 m strip (dependent on lobster density) alongside either side of the leaded rope. All captured lobsters are measured (carapace length) and all lobsters of ≥20 mm carapace length are sexed. The complexity and suitability of the habitat is assessed in the 5 m sections (e.g. rocky reefs, sand, large boulders).USE LIMITATION:To ensure scientific integrity and appropriate use of the data, we would encourage you to contact the data custodian.
Tell us what you think!
GEO.ca is committed to open dialogue and community building around location-based issues and topics that matter to you.
Please send us your feedback