Thank you, members of the committee, for allowing me to speak to you today concerning what science knows about striped bass and planned science activities moving forward.
My name is Doug Bliss, and I am the director of the science branch for the gulf region of Fisheries and Oceans Canada. It's our scientific staff, located in Moncton, New Brunswick, and our Miramichi River research station, located at South Esk, who conduct the federal government's striped bass science program in the southern Gulf of St. Lawrence.
I'll start by briefly showing the range and distribution of this native species. Striped bass is a saltwater bass, and is native to the Gulf of St. Lawrence. Striped bass, with all other diadromous species that live in both fresh and salt water, including Atlantic salmon, have evolved together in rivers in eastern North America since the retreat of the last ice age. You can see in this range map a graphic showing the extent of striped bass, ranging from northern Florida to Canada. We are at the northern extent of its range.
Generally speaking, our striped bass are shorter, smaller, and shorter-lived than those found in the United States, where the the core of their population live. Many of you will know of the seasonal movements of striped bass in the Miramichi River. After spawning, they leave the river and migrate to coastal areas to feed. In the late fall, they return to estuaries, not just the Miramichi, and spend the winter under the ice in what we call a torpid state. That means they do not move very much, nor do they feed until waters start to warm up. Upon spawning in the northwest Miramichi River, typically mid-May to mid-June, they rapidly move to the sea and repeat their annual cycle.
We have records of striped bass being harvested commercially in the southern Gulf of St. Lawrence dating back 102 years, as illustrated in this graphic. Note the pattern of high harvest being followed by declining harvests a hundred ago in the 1920s, and more recently in the 1980s. Through such harvest records, we infer that population levels follow similar trends.
In the interest of time, I will not dwell on this slide about the status of species at risk or of striped bass, but I will just say that in 2012, seven years ago, all the populations of striped bass in Canada were assessed to be at some level of risk of extinction.
With regard to striped bass abundance, Fisheries and Oceans Canada scientists have been monitoring the spawning population of striped bass in the Miramichi since 1994. This is a 24-year dataset consistently measured in the same way every year, and so it is the only reliable indicator of whether the striped bass population in the southern gulf is growing or shrinking. You will notice that we started monitoring striped bass in 1994, before the population crash. The population crashed in 1996, and was at critically low levels for five years. This was followed by some modest growth for another six years, after which there was consistent growth trend after 2006, peaking in 2017.
If we have learned something about this species in the last two decades, it is that it can go through rapid population increases and decreases in relatively short periods of time. Why this happens is something we are seeking to understand. This is why it is important, when considering the status of a population of fish or other wildlife, to look at the trend over a number of years. The population estimates for the upcoming year, 2019, which we will produce at the end of this calendar year, will be very important for us to assess whether the population seems to be continuing to increase, decrease, or stabilize.
Last, I would like to take a moment to explain our federal science activities and to let you know of our plans to conduct more science on this species. We have been monitoring the adult striped bass in a consistent way since 1994. We tag striped bass every year in order to monitor their movements in the southern Gulf of St. Lawrence and, more recently, farther north. We have tried to determine whether there are other established spawning areas for striped bass a number of years ago, but we will undertake such studies once again. We have directly measured the consumption of salmon young, or smolts, and many other species by striped bass. We have worked in partnership with other organizations, such as the Atlantic Salmon Federation, on determining indirect estimates of predation. We plan to continued such collaborative studies on diet. We are using technologies that were not available to us even a few years ago to better understand striped bass and their habitats.
Currently, we are undertaking proof-of-concept development of environmental DNA to easily test for the presence or absence of striped bass in rivers. We are transferring our expertise in acoustic measurements of fish for marine species such as herring and applying this technology on the river, advancing technology on the river to see if we can more accurately and rapidly assess the population of striped bass adults before the fishing season. The picture on the lower right corner of the slide indicates our crew out there in the winter testing this technology through the ice on the Miramichi River.
We intend to do much of this new science in collaboration with interested research and science partners. Our proposed science plan is split into three parts to provide biological reference points for the species; to examine or re-examine recurring questions about the species, such as striped bass diet measurements and assessing whether other spawning areas exist; and finally, to undertake focused studies to understand the environmental stresses and ecosystem dynamics influencing this and many other species.
Thank you.
