Marine

U of T marine biologist dives deep in pursuit of ocean conservation data

Christopher.Sorensen — Thu, 14 Sep 2023 13:50:07 +0000

U of T marine biologist dives deep in pursuit of ocean conservation data

Christopher.Sorensen Thu, 09/14/2023 - 09:50

Cutline

U of T Mississauga Assistant Professor Cassidy D’Aloia, right, and PhD student Taylor Naaykens, left, take a selfie underwater after completing a successful field season (photo by Cassidy D’Aloia)

Ali Raza

Topic

Our Community

Biology

Marine

Oceans

Sustainability

U of T Mississauga

Subheadline

Cassidy D’Aloia studies the population impact of larvae that travel far from their place of birth via ocean currents

Cassidy D’Aloia dives deep to learn about life under the sea, yielding critical data and research for marine conservation efforts.

An assistant professor of biology at the �ؿ�ζSM Mississauga, D’Aloia studies the molecular ecology of coastal fishes and invertebrates and tries to understand the patterns, causes and consequences of dispersal and gene flow in the ocean.

Put simply, she tries to understand where the offspring of sea organisms wind up – whether fish, molluscs or echinoderms – and how larvae move around in ocean currents.

“Do you eat fish? Do you want to keep eating fish? Then dispersal data is important if you want to predict how fish populations will fare for the future,” says D’Aloia, who joined U of T Mississauga last year after completing her postdoctoral work.

As part of her research, she runs the D’Aloia Lab, where she and a team of graduate students work at the intersection of marine ecology, evolution and conservation biology, asking many interdisciplinary questions with answers that have profound implications for the future of marine life and conservation efforts.

D’Aloia examines the sea floor on the hunt for fish (photo by Taylor Naaykens)

Scuba diving in the coral reefs

D’Aloia and her team often collect ocean life data by scuba diving. Dives have taken place in the southern Caribbean Sea off the coast of Belize or Curaçao, or in the North Atlantic off the coast of eastern Canada. Because much of their field work focuses on organisms living in coral reefs, they see firsthand the effects of climate change on the health of these ecosystems.

Diving off the coast of Belize this past summer, D’Aloia says she saw how damaged coral reefs have become.

“Corals are critical to marine biodiversity,” she says. “Rising ocean temperatures are a huge problem for coral reefs because of the impact. We study a lot of things that live on corals and this year the coral bleaching was bad.”

Coral bleaching happens when the water becomes too warm and corals expel algae living in their tissues, causing them to turn completely white. While the bleaching doesn’t necessarily kill the corals, it places them under more stress and makes them vulnerable to disease. That, in turn, can impact other species that are dependent on them, including humans that rely on the ocean for their livelihoods.

A healthy reef with high cover of living coral off the coast of Curaçao (photo by Cassidy D’Aloia)

An average day in the field in Belize involves waking up at 6 a.m. to eat breakfast and ready the scuba equipment before getting to the water by 8 a.m. From there, D’Aloia and her team swim out to the coral reef and begin diving where they record data, map populations and collect tissue samples from tiny organisms for genetic analysis.

With a few breaks in between, the team makes deep dives three times a day before heading back to the field station by 4 p.m. to clean the gear, back up data, make dinner and sleep. The field work goes on six days a week for a month or two.

“Our field work is gruelling,” D’Aloia says. “But I just love it. Being in the field is by far the best part of the job. It’s a very special feeling being underwater – like visiting another planet. It’s a real privilege to be able to do that.”

D'Aloia has worked in Belize for many years, building and strengthening relationships with local fishers, the University of Belize and other researchers. Her work has led to several partnerships, including Fisheries and Oceans Canada. She works with the federal government department to develop science-based management plans for Canada’s fish stocks.

D’Aloia’s current research in Belize is funded by the Belize Fund for a Sustainable Future and U of T Mississauga, in collaboration with the University of Belize’s Environmental Research Institute.

A coral-dwelling fish (Elacatinus evelynae) sitting atop a healthy coral (photo by Cassidy D’Aloia)

The importance of data

To understand how larval development of marine life is connected to conservation efforts, D’Aloia explores the consequences of larvae travelling far from their place of birth on ocean currents.

“We’re interested in how organisms move in the very early part of their life cycle,” she says. “It sounds simple, but it’s a tricky problem in marine biology.”

Larval dispersal determines how populations change over time and how they evolve. Species studied include snails, gastropods, cod, American lobster, sea cucumbers, hogfish and conch fish.

“Fish and harvested invertebrates are one of the last wild animals we still harvest in their natural environment, so I think it lends itself well to the integration of science and policy and trying to work together to give the fundamental scientific data that can help us make sustainable choices,” D’Aloia says.

“If we want to make decisions on spatial conservation, then you need this data.”

D’Aloia grew up in New York state, away from the ocean, but says she always loved science and biology. As a result of great high school teachers and encouraging university professors, she sought to become a marine biologist and “fell in love with the ocean.”

PhD student Taylor Naaykens runs surveys and counts fish underwater (photo by Cassidy D’Aloia)

Now an assistant professor overseeing a team of graduate students, she offers training and support for students to conduct research and build their careers as marine biologists. That includes learning how to scuba dive.

“Research that can support the conservation of those ecosystems is so important,” D’Aloia says. “I think supporting students who are trying to pursue good research and want to make a difference in the world is a good thing.”

Ouch! U of T paleontologists identify 508-million-year-old sea creature with can opener-like pincers

ullahnor — Wed, 26 Apr 2017 15:39:11 +0000

Ouch! U of T paleontologists identify 508-million-year-old sea creature with can opener-like pincers

ullahnor Wed, 04/26/2017 - 11:39

Cutline

Reconstruction of “Tokummia katalepsis” showing a pair of large pincers at the front for capturing prey with much of the multi-segmented body protected by a hardened shell (illustration by Lars Fields)

Sean Bettam

Author legacy

Sean Bettam

Topic

Breaking Research

Fossils

Marine

Faculty of Arts & Science

Paleontology

Ecology & Evolutionary Biology

Earth Sciences

Subheadline

Discovery points to origin of millipedes, crabs and insects among other species

Paleontologists at the �ؿ�ζSM and the Royal Ontario Museum (ROM) have uncovered a new fossil species that sheds light on the origin of mandibulates, the most abundant and diverse group of organisms on Earth, to which belong familiar animals such as flies, ants, crayfish and centipedes.

The finding was announced in a study published today in Nature.

Read more at The Guardian

Tokummia documents for the first time in detail the anatomy of early “mandibulates,” a hyperdiverse sub-group of arthropods that possess a pair of specialized appendages known as mandibles, used to grasp, crush and cut their food. Mandibulates include millions of species and represent one of the greatest evolutionary and ecological success stories of life on Earth.

“In spite of their colossal diversity today, the origin of mandibulates had largely remained a mystery,” said Cédric Aria, lead author of the study and a recent graduate of U of T's PhD program in the Faculty of Arts & Science's department of ecology & evolutionary biology. “Before now, we’ve had only sparse hints at what the first arthropods with mandibles could have looked like and no idea of what could have been the other key characteristics that triggered the unrivalled diversification of that group.”

The creature lived in a tropical sea teeming with life and was among the largest Cambrian predators, exceeding 10 centimetres in length fully extended.

An occasional swimmer, its robust anterior legs made it a preferred bottom-dweller, like lobsters or mantis shrimps today. Specimens come from 508 million-year-old sedimentary rocks near Marble Canyon in Kootenay National Park, British Columbia. Most specimens at the basis of this study were collected during extensive ROM-led fieldwork activities in 2014.

“This spectacular new predator, one of the largest and best preserved soft-bodied arthropods from Marble Canyon, joins the ranks of many unusual marine creatures that lived during the Cambrian explosion, a period of rapid evolutionary change starting about half a billion years ago when most major animal groups first emerged in the fossil record,” said co-author Jean-Bernard Caron, senior curator of invertebrate paleontology at the ROM and an associate professor in the departments of ecology & evolutionary biology and earth sciences at U of T.

This specimen of Tokummia katalepsis shows a number of strong legs on the left partially protruding from the body, the shape of the bivalved carapace and dozens of small paddle-like limbs below the trunk at the lower right. This nearly complete fossil was chosen as the main reference for the new genus Tokummia and new species katalep (photo courtesy of Jean-Bernard Caron)

Analysis of several fossil specimens, following careful mechanical preparation and photographic work at the ROM, showed that Tokummia sported broad serrated mandibles as well as large but specialized anterior claws, called maxillipeds, which are typical features of modern mandibulates.

“The pincers of Tokummia are large, yet also delicate and complex, reminding us of the shape of a can opener with their couple of terminal teeth on one claw and the other claw being curved towards them,” said Aria, who is now working as a post-doctoral researcher at the Nanjing Institute for Geology and Palaeontology in China. “But we think they might have been too fragile to be handling shelly animals and might have been better adapted to the capture of sizable soft prey items, perhaps hiding away in mud. Once torn apart by the spiny limb bases under the trunk, the mandibles would have served as a revolutionary tool to cut the flesh into small, easily digestible pieces.”

The body of Tokummia is made of more than 50 small segments covered by a broad two-piece shell-like structure called a bivalved carapace. Importantly, the animal bears subdivided limb bases with tiny projections called endites, which can be found in the larvae of certain crustaceans and are now thought to have been critical innovations for the evolution of various legs of mandibulates and for the mandibles themselves.

The specimen shows a pair of large pincers (maxillipeds) at the front preserved almost symmetrically. The anterior walking appendages are covered by the large carapace. Posterior appendages would have been used for occasional swimming and maybe a respiratory function. The trunk ends in a furcate tailpiece. (photo courtesy of Jean-Bernard Caron)

The many-segmented body is otherwise reminiscent of myriapods, a group that includes centipedes, millipedes and their relatives.

“Tokummia also lacks the typical second antenna found in crustaceans, which illustrates a very surprising convergence with such terrestrial mandibulates,” said Aria.

The study also resolves the affinities of other emblematic fossils from Canada’s Burgess Shale more than a hundred years after their discovery.

“Our study suggests that a number of other Burgess Shale fossils such as Branchiocaris, Canadaspis and Odaraia form with Tokummia a group of crustacean-like arthropods that we can now place at the base of all mandibulates,” said Aria.

The animal was named after Tokumm Creek, which flows through Marble Canyon in northern Kootenay National Park, and is the Greek for “seizing.” The Marble Canyon fossil deposit was first discovered in 2012 during prospection work led by the Royal Ontario Museum and is part of the Burgess Shale fossil deposit, which extends north into Yoho National Park in the Canadian Rockies. All specimens are held in the collections of the Royal Ontario Museum on behalf of Parks Canada.

The Burgess Shale fossil sites are located within Yoho and Kootenay national parks in British Columbia. The Burgess Shale was designated a UNESCO World Heritage Site in 1980. Parks Canada protects these globally significant palaeontological sites and works with leading scientific researchers to expand knowledge and understanding of this key period in the Earth's history. New information from ongoing scientific research is continually incorporated into Parks Canada's Burgess Shale education and interpretation programs, which include guided hikes to the fossil sites.

Funding for the research was provided primarily by a Natural Sciences and Engineering Research Council of Canada Discovery Grant to Caron, and Royal Ontario Museum fieldwork grants.

Cédric Aria (left) and other crew members are splitting layers of shale from the Marble Canyon quarry site in the hopes of revealing new fossils and then cataloguing the specimens for further examination back at the museum (photo courtesy of Jean-Bernard Caron)

Efforts to protect marine ecosystems thwarted by lack of funding, staff: U of T part of international study

ullahnor — Thu, 20 Apr 2017 17:44:46 +0000

Efforts to protect marine ecosystems thwarted by lack of funding, staff: U of T part of international study

ullahnor Thu, 04/20/2017 - 13:44

Cutline

Looking towards the surface of schooling coral reef fish in some of the world's most diverse coral reefs in Raja Ampat, Indonesia (photo courtesy of Emily Darling/Wildlife Conservation Society)

Sean Bettam

Author legacy

Sean Bettam

Topic

Global Lens

Marine

Faculty of Arts & Science

Ecology & Environmental Biology

Establishing Marine Protected Areas (MPAs) along coastlines and oceans worldwide are an increasingly popular strategy for protecting marine habitats and biodiversity.

However, a new global study demonstrates that widespread lack of personnel and funds are preventing MPAs – which include marine reserves, sanctuaries, parks and no-take zones – from reaching their full potential.

“From our survey of nearly 600 locations, we found only nine per cent of MPAs with available management data reported having adequate staff, and only 35 per cent reported acceptable funding levels,” said Emily Darling, a postdoctoral researcher in ecology & evolutionary biology at the Faculty of Arts & Science and associate conservation scientist at Wildlife Conservation Society.

She is part of an international team of contributors to the study published in Nature last month. After four years compiling and analyzing data on site management and fish populations in MPAs around the world, the researchers discovered that shortfalls in staffing and funding are hindering the recovery of MPA fish populations.

“We were alarmed to learn how just a few sites report having sufficient human and financial resources to operate successfully,” said Darling. “It highlights the need for further investment of practical resources for conservation,” said Darling.

Emily Darling completes a coral reef survey in Indonesia (photo courtesy of Emily Darling/Wildlife Conservation Society)

Lead author David Gill, who conducted the research during a postdoctoral fellowship supported by the National Socio-Environmental Synthesis Center (SESYNC) and the Luc Hoffmann Institute, said the study identified critical gaps in the effectiveness and equity of MPAs.

“We set out to understand how well marine protected areas are performing and why some perform better than others,” he said. “What we found was that while most marine protected areas increased fish populations, including MPAs that allow some fishing activity, these increases were far greater in MPAs with adequate staff and budget.”

While fish populations grew in 71 per cent of MPAs studied, the level of recovery of fish was strongly linked to the management of the sites. At MPAs with sufficient staffing, increases in fish populations were nearly three times greater than those without adequate personnel.

Such increases in fish populations as a result of greater investments could translate into futher benefits for tourism ventures within an MPA, as well as for fishing operations beyond protected areas, researchers say.

Coral reef fish support productive fisheries and local livelihoods for coastal communities around the world (photo by David Gill)

Marine protected areas are rapidly expanding around the world.

In 2011, 193 countries – including Canada – committed themselves to the Convention on Biological Diversity Aichi Targets, including a goal of “effectively and equitably” managing 10 per cent of their coastal and marine areas within MPAs and “other effective area-based conservation measures” by 2020. In the last two years alone, over 2.6 million square kilometers have been added to the portion of the global ocean covered by MPAs, bringing the total to over 14.9 million square kilometers.

The Department of Fisheries and Oceans Canada, the agency tasked with managing MPAs nationally, estimates that 0.8 per cent of Canada's waters are protected within MPAs, with less than 0.1 per cent being fully protected from fisheries extraction.

“We have a long way to go to meet international commitments towards protecting 10 per cent of Canada's oceans, but there is exciting momentum building for this,” said Darling, a Canadian whose expertise is in using collaborative big data to investigate the effects of climate change on coral reef ecosystems and the coastal livelihoods they support.

But Darling and her colleagues on the study caution that any increase in the numbers of MPAs by any country must be adequately supported in terms of staffing and operational funding, and it must not come at the expense of existing sites.

Emily Darling records the three-dimensional architecture of different species of corals in Kenya (photo courtesy of Emily Darling)

The researchers propose a number of policy solutions – including increasing investments in MPA management, strengthening methods for monitoring and evaluation of MPAs, and prioritizing social science research on MPAs.

Ultimately, the authors see an opportunity for individual nations to work together at a global level to protect a resource that is shared and used by societies worldwide.

“People around the world depend on marine resources that are managed fairly and effectively. With global collaborations, we can identify strategic future investments in marine protected areas, and track progress towards better social and ecological outcomes,” said Darling.

The research was supported by the National Socio-Environmental Synthesis Center (SESYNC), under funding received from the National Science Foundation. Darling was supported by a David H. Smith Conservation Research Fellowship and the Cedar Tree Foundation prior to her current Banting Fellowship.

Marine

U of T marine biologist dives deep in pursuit of ocean conservation data

Scuba diving in the coral reefs

The importance of data

Ouch! U of T paleontologists identify 508-million-year-old sea creature with can opener-like pincers

Read more at the Globe and Mail

Read more at The Washington Post

Read more at The Guardian

Efforts to protect marine ecosystems thwarted by lack of funding, staff: U of T part of international study