Green Crab Control Management Trapping and Population Prevalence in St. Mary’s Bay
The European Green Crab (Carcinus maenas) is an aquatic invasive species in Canada. In Newfoundland, green crab were first confirmed in 2007 in the northern regions of Placentia Bay. Since the initial discovery, the Department of Aquatic Invasive Species at Fisheries and Oceans Canada has conducted controlled management trapping and population prevalence assessments across Newfoundland. In the St. Mary’s Bay region, the presence of green crab was confirmed by fisheries and oceans in 2019 in the waters of Riverhead, O’Donnells, and Salmonier Arm (St. Joseph’s & Mt Carmel). Northeast Avalon ACAP has partnered with Fisheries and Oceans Canada to continue trapping and collecting data on the population prevalence of green crab in the St. Mary’s Bay region over the last two field seasons.
Green crab can be identified and distinguished from other crab species by the five spikes on either side of their eyes on the carapace or shell. Green crab is small to medium in size, and the maximum carapace width is 10 centimeters. Do not let the name fool you, green crab can range from green, to brown, to orange, and red. Colouration often depends on how recently the crab has molted. The native species, Rock crab, is the most common species that is confused with the invasive green crab. Rock crab can be distinguished from green crab by the rock crabs more scallop-shaped carapace consisting of nine rounded lobes on either side of the eyes instead of the five spikes seen in green crab.
The invasive green crab poses a serious threat to native species and coastal habitats. Green crab have aggressive behavior and outcompete native species, such as Rock crabs. Green crab have a wide-ranging diet including young rock crab, young lobsters, and native fish species. During foraging and burrowing, green crab destroy eelgrass beds with accounts for 100% destruction of eelgrass bed habitat with the introduction of green crab to an area. Eel grass beds are critical habitat for several native species including Atlantic Cod which uses eel grass beds as fish nursury habitat. Furthermore, due to the green crab’s reproductive potential, large range of environmental tolerance, and their aggressive behaviour, once a green crab population has etablished itself in an area it is almost possible to ensure complete removal.
A female green crab can spawn up to twice in one season, spawning 185,000 eggs at a time. Green crab can survive in brackish waters and have been caught in inlets such as Cootes Pond. Green crab can also survive out of water for several days while attached to fishing gear, boats, and other marine apparatus, and therefore it is protocol to freeze green crab for a total of five days to ensure termination.
While working in the St. Mary’s Bay region, Northeast Avalon ACAP have successfully removed 2438 green crab in 2022. In 2023, we removed an additional 2823 green crab from the St. Mary’s Bay region. Over the two years we visited several sites including; Colinet, Cootes Pond, Mall Bay, Mitchell’s Brook, Mount Carmel, St. Josephs, and Riverhead. We set 135 traps in 2022, and this year we over doubled our catch effort and set 352 traps.
To learn more about the invasive European Green Crab click here to open the DFO’s website on Green Crab.
Assessing the Habitat Quality for Atlantic Salmon in the Waterford River
Atlantic salmon once thrived in the Waterford and neighboring urban rivers, and following rapid urbanization within the last 100 years, the rivers faced significant levels of pollution, redirecting by development, and in some areas they were completely tunneled over. Significant efforts have been made in recent years to restore these watersheds to their natural glory, and several attempts have been made to reintroduce Atlantic salmon to the Waterford River, Rennies River, and Virginia River. However, as the climate begins to change for the Northeast Avalon, evidenced by mild winters with significant hydrological events and warmer dry summers, this project aims to assess how the climate has impacted the structure and quality of the river, and whether or not the Waterford River is able to support future Atlantic salmon reintroduction attempts in its current state and determine what habitat enhancements at the lower reaches of the river could be proposed to increase salmon returns. One limitation is the effect and presence of predatory brown trout on future reintroduced Atlantic salmon. Therefore, we approach this project as having stages, where once we determine the habitat quality and potential need for any habitat enhancements through this proposal, we recommend future stages to include electrofishing to determine the fish stock currently present in the Waterford River, in order to decide whether or not predation by brown trout would out compete reintroduced salmon. The final stage would be to begin an Atlantic salmon reintroduction program and subsequent stock monitoring.
This one-year project funded by The Atlantic Salmon Conservation Foundation, proposes to identify and assess barriers to salmon migration, monitor water quality, and assess damage/changes to the riverbed of the lower reaches of a St. John’s urban historic salmon river, the Waterford River. This comes in response to the changing seasonal fluctuations in precipitation and temperature, in addition to increasingly common extreme hydrological events as predicted in climate change forecasts for Eastern Newfoundland. The goal of the project is to assess the viability of future habitat enhancements to ensure successful salmon introductions in the years to come. Emphasis will be placed throughout the project on public engagement through activities such as river clean-ups, litter characterizations, and the collection of citizen data to understand how this winter’s high-water marks compares to historical data. Finally, through partnerships with local organizations they hope to share their findings publicly through seminars and workshops, in addition to a final report shared on NAACAPs website.
Waste Capture and Audit of catch basin LittaTraps(TM) in Downtown St. John’s, NL
Plastic is a part of everyday life for most Canadians and is an integrated part of the world’s economy given the material’s versatility, durability, and low manufacturing costs. However, on April 23, 2021, the Canadian Environmental Protection Act, 1999 added plastic manufactured items as a schedule 1 toxic substance. This addition was supported by increasing evidence that the release of plastic waste into the environment through activities such as littering, flooding, or accidental release (ex. Wind), poses an ecological hazard, including physical harm, to some animals and their habitat1. Given the nature of plastic pollution and the connectivity of terrestrial and aquatic ecosystems, plastic pollution that occurs on land is often carried by rainwater, to catch basins, and into streams, rivers, and oceans. There is a lack of information regarding the seasonal and spatial variability of inorganic debris, particularly macro-plastics accumulation, in downtown St. John’s. Macro-plastics, referred to as being plastic that is larger than 5mm in size, account for the majority of plastic emissions volume into oceans and warrant further examination. An approach that characterizes and quantifies macro-plastics, and their spatial and seasonal variability can provide valuable information that can inform better waste diversion and waste management practices.
In a new project that builds on the organization’s previous waste diversion and reduction initiatives, funded by Fisheries and Oceans Canada (DFO), NAACAP is communicating closely and consulting with the City of St. John’s when deploying and auditing inorganic debris that accumulates in LittaTrapsTM in catch basins at 30 locations across downtown St. John’s. This debris will be systematically collected, photographed, and categorized according to trash collection and audit protocols developed by NAACAP, in collaboration with DFO. Collection and audits will be completed on a minimum monthly basis, with more frequent collection in the first month following installation, and as needed based on debris accumulation and the occurrence of extreme weather events. Sampling will occur throughout the summer and fall of 2021 to help establish seasonal variability, if any, in debris in downtown St. John’s.
In addition to diverting inorganic waste from the ocean, and the generation of valuable insight into debris accumulation in the St. John’s urban center, this project will provide opportunities for public and industry outreach. In an effort to engage the public and local interest in marine conservation, trash audit data will be shared on social media (no data will be shared on social media with respect to individual businesses), as well as on open-source data platforms such as Marine Debris Tracker, in order to foster awareness of litter accumulation in downtown storm drains, and subsequent runoff into the St. John’s Harbour. A final report summarizing all monthly trash audit data will be created and shared on NAACAP’s website and social media upon completion of this project.
Final Report: Waste Capture and Audit of Catch Basin LittaTrapsTM in Downtown St. John’s, NL 2020-22: PDF Format
Enviropod website link: https://www.enviropod.com/
Northeast Avalon Watersheds – Plastic Waste Reduction and Diversion Project
The Northeast Avalon region is the most densely populated area in Newfoundland and Labrador; it is also home to Canada’s windiest city (St. John’s) and is a region slow to make adaptations to dealing with waste. A recent garbage audit of provincial government offices by the Multi-Materials Stewardship Board (MMSB) found that, on average, employees in the province’s Confederation Building produced over 1.5 kg of garbage a day, and after organics, the largest category of waste produced there included food and beverage packaging, plastic bags, and plastic cutlery.
Beyond the confines of this and other office buildings, where waste usually finds its way to the appropriate facilities, waste in this category has an outsized representation on our streets, in our ditches and in our waterways. Plastics, plasticised cardboard, styrofoam, and other petrochemical derived products are light, often flat, and often contain food residue, making them targets for redistribution by wildlife, the wind, or both. The combination of plentiful plastic waste that comes freely available to consumers with food and products, and often inadequate on-street garbage/recycling receptacles, makes for ongoing issues around the amount of garbage in our environment. When plastic debris enters waterways, it further exacerbates urban water quality by: a) leaching chemicals to the water, b) clogging water flows, c) reducing aquatic habitat for fish and invertebrates, d) being mistaken for food by vertebrate fauna, and e) lessening the enjoyment of the area.
This project will use two methods for removing garbage from two local watersheds – those of the Waterford and Virginia Rivers – in order to improve these target ecosystems and gather data on the types of locally generated garbage affecting our urban waterways. With this “trash data”, we will target ‘upstream’ sources of plastic pollution by engaging with local businesses on plastic packaging alternatives.
Throughout the summer, we will be organising clean-up events along the Waterford and Virginia Rivers with local schools, youth groups, community groups, or whoever else wants to roll up their sleeves with us! We will also be installing debris-collecting floating booms on each of these rivers during July and August to track and remove any floating debris making its way downstream. We’ll be helped out by a CCNL Green Team this summer, who will be coordinating and conducting clean-ups, monitoring our debris booms, keeping our “trash data” up-to-date and researching some plastic packaging alternatives for our business outreach activities this fall and winter.
If you’re involved with a community and/or youth group, and you’d like help organising a clean-up activity, or if you would like to help us by contributing some “trash data”, get in touch with us!
ALSO, if you’re involved with a Chamber of Commerce, Rotary Club, or other type of business group and you’d like to hear about alternatives to plastic packaging, let us know and we’ll be happy to present at one of your meetings!
Shoreline Environmental Baseline Surveys in Placentia Bay, NL: A shoreline characterization and assessment of biogeochemistry, nutrients, coliforms, and hydrocarbons
Placentia Bay, on the Southeast coast of Newfoundland is formed by the Burin Peninsula on the west and the Avalon Peninsula on the East, and is the largest bay in Newfoundland. It has been identified as a Priority Area for Integrated Management Planning by the Department of Fisheries and Oceans, in part due to its status as one of Canada’s largest marine oil handling areas. This coastal area is critical to the future economic development of Newfoundland and Labrador for marine activities such as commercial fishing and aquaculture, fabrication, refining, transportation, and tourism potential. The unique geomorphology of the coast and influence of Gulf Stream waters make Placentia Bay productive habitat for marine life. This marine ecosystem is home to hundreds of species, and has provided a sustainable livelihood for indigenous people and settlers for hundreds of years. Sustainable development in this area relies upon an understanding of the health and condition of the Placentia Bay marine and coastal environment, and baseline data is an important first step in detecting changes related to management and external impacts.
NAACAP’s role in Placentia Bay is to fill a recognised data-gap by collecting and supplying baseline data for one of the six important marine ecosystem areas in the country that currently experience a high volume of traffic within the Federal Government’s Oceans Protection Plan.
Map of Real-Time Marine Traffic in Placentia Bay (source: marinetraffic.com)
To provide scientific data pertaining to the current state of the Placentia Bay, NAACAP is embarking upon a Shoreline Environmental Baseline Program focused on assessing shoreline character and seawater properties. The sampling program will be carried out at 8 representative coastal sites around the Bay, 4-times per year, over a 3 ½ -year period from October 2018 to March 2022.
NAACAP is partnering with Dr. Rachel Sipler (CRC, Chemical Oceanographer) of the Ocean Science Centre, Memorial University, the Chemical Analysis and Microbiology Laboratory at Marine Institute, Melanie Irvine, Project Geologist with the Geological Survey of NL. Together, we will be collecting and analyzing data on:
- The sensitivity of select beaches to erosion, storm surges, and petroleum contamination, and how these characteristics change over time.
- Nearshore biogeochemistry and nutrient levels at sites around Placentia Bay at times corresponding with high and low freshwater inflow periods. We will use a sonde probe and taking seawater samples for analysis in the lab, looking specifically at:
- Dissolved Organic Carbon (DOC)
- pH calculated from Total Inorganic Carbon (TIC) and Total Alkalinity (TAlk)
- Dissolved Oxygen (DO)
- Total Dissolved Nitrogen (TDN)
- Nutrients (ammonium, nitrate, nitrite, urea, phosphate, silica)
- Coliform bacteria
- Total Hydrocarbon (THC) levels. We will collect, process, and analyze barnacles, which are long-lived sessile filter-feeding invertebrates that tend to bioaccumulate marine contaminants and are useful bioindicators
The results of this project will not only provide a publicly open source of data that can characterize ecosystems, but may also support evidence-based decision-making, such as assessments for marine spatial planning around conservation and the cumulative effects of anthropogenic activities. This baseline data will help differentiate between general background levels or conditions in the marine environment and responses to increased anthropogenic activity or climate change, and NAACAP looks forward to contributing to building capacity of key parties to collect environmental data as part of the implementation of the Oceans Protection Plan.