A win for mobulid rays at CITES Convention of Parties

Every now and then a breakthrough happens! That was the case at the 17th Conference of the Parties to the Convention on International Trade in Endangered Species (CITES) in Johannesburg, South Africa, in October 2016.

In the fight to protect our most threatened marine species (sharks and rays), regulation of international trade is viewed as a key element, because much of current trade happens unseen and unrecorded. Therefore, a listing under CITES – either Appendix I, banning trade, or Appendix II, regulating trade – is often part of a species-level conservation plan. Convincing nations (parties) to agree to regulate trade of a threatened species might sound like a no-brainer – but it often involves a heavy burden when it comes to implementation. Therefore, a CITES listing isn’t the only recourse or even the best path when conserving marine species. On the other hand, it is a global recognition of the problem, and can be a signal of progress.

This is especially true in the context of prior CITES Conference of Parties. In the past, proposals to list marine species have been rejected because the data – the evidence – for population declines was deemed to be inadequate. After all, migratory, pelagic species are hard to monitor! In fact, precautionary listings were viewed as all but impossible when it came to commercially traded marine species. (Incidentally this was not the case for many terrestrial species such as rare plants.) Navigating the twisty path toward effective regulation of commercially traded sharks and rays (that are also threatened) has been a challenge for policy folks.

This year was a banner year for 13 species of sharks and rays, all of which were listed on Appendix II. A lot of people worked incredibly hard on pulling that off. I became involved in sorting through the evidence for declines for the proposal to list the nine mobulid ray species (Mobula spp). These rays have been fished heavily for their gill plates following the listing of Manta spp (their relatives) on Appendix II in 2013 (see, a twisty path!). In preparation for the Mobula proposal, my colleagues and I pulled off a risk analysis of the only population of a Mobula species (M. japanica) for which we have size and age data (see Pardo et al. 2016b). This provided a bit of quantitative evidence of the serious threat unregulated fishing poses to these rays. We worked hard to complete this (and publish it!) before the Conference of Parties this year in the hopes it would help – and we weren’t disappointed!

It’s possible that the successful listing of the nine Mobula species – plus silky shark, and three species of thresher – are signs of increasing motivation to regulate the trade of our most threatened (and traded) marine species. The IUCN has more information on that. In the meantime, I am hopeful that the fates of mobulid rays are more secure.

Inferring the conservation status of tuna, grouper, and shark and ray species

2015 was a challenging year! It all paid off when my collaborative grant proposal with Jason Matthiopoulos at U Glasgow, Marc Mangel at UC Santa Cruz, and Nick Dulvy at Simon Fraser was funded by the NSF Division of Environmental Biology in December.

So what did we propose to do? We are interested in inferring the population dynamics of marine fishes that are hard to census. This means large, high value fishes that are vulnerable to overfishing because of their biology. For example, one third of shark and ray species are known to have declined in recent history, but it is unknown whether most of the remaining two-thirds are also declining, or if they are stable. Likewise, population sizes of predatory fishes such as groupers and tuna have decreased substantially due to intense fishing, yet we know little about the extent of decline and risk of extinction for some of these species. This knowledge gap impedes management efforts, such as limits on catch and trade.

But we have another type of information about these fishes: their reproductive behavior, lifespan, and metabolic rates, which vary uniquely within each clade. I worked closely with my collaborators to come up with a new way to leverage this type of information to infer demographic rates and project species’ status. Previous efforts to do this have not incorporated the unique details of each species’ biology, such as gill area (which affects metabolism) and reproductive mode (such as viviparity). My contribution to the project will be to develop theory linking the evolution of these traits to demographic rates. We will then infer the unknown demographic parameters – i.e., natural mortality – from species traits (using Approximate Bayesian Computation). These estimates will be used as priors to inform species status projections for each group. More modern statistical methods (Bayesian state-space models) will allow information from models of data-rich species – which have formal assessments – to be shared with poorly studied species in similar habitats, or with relatives. With this new understanding of population trajectories, the team will produce recommendations for use by organizations like the IUCN.

This is a very ambitious project that will involve staff, postdocs, and a lot of outreach activity. We are very excited about the potential to make a fundamental contribution to the conservation of these species, and to our basic understanding of fish life history evolution. Stay tuned!

Wrasse societies on PBS

PBS Nature just aired a short segment on the ocellated wrasse (one of the fish I study) for their documentary series on Animal Homes. Their crew came to Corsica to learn about the wrasse and shoot its social interactions – and interview my collaborator Suzanne Alonzo – underwater. The footage is in the episode on Animal Cities, which one can see for free here.

The video quality is great, and they do a decent job of explaining the how the male mating tactics and female preferences co-evolved. We had a very nice time with the crew and the host, Chris Morgan, introducing them to the animal soap opera that takes place every year in this system!

All the drama takes place below the surface:
med mackerel

Read like a butterfly, write like a bee

The title comes from Philip Pullman. Of course it derives from the Ali quote, “Float like a butterfly, sting like a bee.” I first heard it from Marc Mangel.

A recent paper (MacNeil et al., Nature April 8, 2015) addresses the state of the world’s coral reef fishes, many of which support small-scale fisheries that are essential livelihoods of coastal human populations. The paper shows that simple forms of fisheries management improve reef health.

With my colleague Nick Dulvy, I wrote a News and Views piece to provide some context. We wanted to point out this is really good news! Simple fishing restrictions (e.g., on gear or species) do work to recover and maintain fish biomass. And we know that as biomass recovers, so do the fish-coral interactions (e.g., grazing and scraping) that are necessary for healthy, resilient reefs.

It is hard, but not impossible, to balance coral reef ecosystem health with human needs. There are nuances to this message. But in the meantime it’s good to have a reminder that we shouldn’t give up!


(Photo is an old one of me doing reef fish fieldwork in French Polynesia)

Writing engagingly (and then promoting your work) (updated!)

I participated in “Demystifying Publishing” – a workshop for the Biology grad students at Simon Fraser University. The students asked me to present on two topics: writing engagingly, and then publicizing or promoting your work. It turns out I have a lot of thoughts on both of these topics – especially on the rapidly changing relationship between social media and academic science.

If you’re interested, click here for a PDF of my talks.

I also compiled a short list of some favorite resources and books on scientific writing.

Scientific writing:
Nature Physics Editorial, 2007. Elements of Style. Vol 3, 581
Greene, AE. 2013. Writing Science in Plain English.
Lertzman 1995 Bulletin of the Ecological Society of America.
Schimel, J. 2011. Writing Science: How to Write Papers That Get Cited and
Proposals That Get Funded

Writing style resources:
Garner, B. 1998. Garner’s Modern American Usage
Strunk W. and White EB. 1918. The Elements of Style.

Help with thesis writing:
Bolker, J. 1998. Writing Your Dissertation in Fifteen Minutes a Day: A Guide to
Starting, Revising, and Finishing Your Doctoral Thesis
Silvia, PJ. 2009. How to Write a Lot: A Practical Guide to Productive Academic

Memoirs on writing:
King, S. 2000. On Writing.
Lamott, A. 1995. Bird by Bird.

update May 2015:

The Chronicle of Higher Education has compiled some short essays on
improving academic writing that are worth reading. [PDF]

Media coverage of paper in Proceedings B

My paper with Suzanne Alonzo in Proceedings of the Royal Society B was picked up by the Canadian popular science media. I was interviewed by multiple people about the broader context of the paper’s results. Most of the headlines came from an article written by the Canadian Press, a news wire service. Interesting to see the media response to a cool topic (paternal care in animals) despite the fact that the paper is all mathematical theory (often difficult to convey to a general audience).

Press coverage screenshots