Possible issue with corals

[gclawson1]

I was having a look and noticed that coral species don't have any impacts reported. Turns out the vulnerability we assign to them is 0, because of the rescaling we do. For context, we rescale any vulnerability between 0 and 0.25 to 0, 0.25 to 0.75 to 0.5, and anything above 0.75 to 1. The vulnerability for all corals species for the bycatch stressor (the stressor we assume, since its not a targeted species) is ~0.13. I was just surprised there were no impacts for any of the coral species, but given our methods it checks out. This is something I wanted to flag as I think it'll be important to explain. Also, I can't imagine we're catching many forage species in coral reef habitat, right??

[bshalpern]

is it maybe worth having a category for true zeros, and one for low but non-zero (0.01 to 0.25)? I agree that forage fish aren't in coral reefs, but there is other bycatch that happens in coral reefs that could get used for feed...

[gclawson1]

Yeah that could be a good option. The reason we chose the 0, 0.5, and 1 values was to match our terrestrial methods:

"For terrestrial species, the IUCN reports the suitability of cropland for species to survive and reproduce (IUCN 2022). We designated habitats as "unsuitable," "marginal," and "suitable," assigning sensitivity values of 1 (full sensitivity), 0.5 (marginal sensitivity), and 0 (insensitivity), respectively (Williams et al., 2021)."

So I think the option for marine would be to either:

• add a category for 0.01 to 0.25; maybe make all of those 0.25 vulnerability
• change the cutoff for assigning 0 values to 0.01, rather than 0.25. So anything between 0.01 and 0.75 would get a vulnerability of 0.5. The only problem here is we may be artificially inflating some impacts, but I guess kind of already do this and its all a model anyways....

[gclawson1]

Just chatted with Julia about this. She agrees that it should definitely be non-zero, and perhaps even greater than 0.25. I think corals should be treated a bit different than the other taxon, because it is both a species and a habitat.

The way I have it set up, the only time coral species would be exposed to fishing is when a benthic gear would be used (e.g., bottom trawling). My proposal is to use the vulnerability value from Butt et al. for habitat loss and degradation for corals, which is ~.61 for all species. Because the only exposure corals would have is with benthic gears, I think this would classify as vulnerability to habitat loss. Is that sufficient justification? We can back it up with other sources too

[bshalpern]

I like this revised plan...

[juliablanchard]

I agree with that too, thanks Gage

---

Professor Julia Blanchard (she/her) ARC Future Fellow Institute for Marine and Antarctic Studies & Centre for Marine Socioecology College of Science and Engineering University of Tasmania

Please note I work Tuesdays-Fridays

E: @.**@.> T: +61 (0)3 62.26.69.32 W: http://www.utas.edu.au/profiles/staff/imas/julia-blanchardhttp://www.utas.edu.au/profiles/staff/imas/julia-blanchard ; http://www.sizeecology.com/ www.sizeecology.comhttp://www.sizeecology.com/

I acknowledge the Traditional Owners of the lands and waters on which I work and live, and pay my respects to the Elders, past and present.

[Logo Description automatically generated with low confidence]

---

From: Gage Clawson @.> Sent: Thursday, 7 December 2023 10:54 AM To: Sustainable-Aquafeeds-Project/feed_biodiv_impact_mapping @.> Cc: Subscribed @.***> Subject: Re: [Sustainable-Aquafeeds-Project/feed_biodiv_impact_mapping] Possible issue with corals (Issue #15)

Just chatted with Julia about this. She agrees that it should definitely be non-zero, and perhaps even greater than 0.25. I think corals should be treated a bit different than the other taxon, because it is both a species and a habitat.

The way I have it set up, the only time coral species would be exposed to fishing is when a benthic gear would be used (e.g., bottom trawling). My proposal is to use the vulnerability value from Butt et al. for habitat loss and degradation for corals, which is ~.61 for all species. Because the only exposure corals would have is with benthic gears, I think this would classify as vulnerability to habitat loss.

— Reply to this email directly, view it on GitHubhttps://github.com/Sustainable-Aquafeeds-Project/feed_biodiv_impact_mapping/issues/15#issuecomment-1843879668, or unsubscribehttps://github.com/notifications/unsubscribe-auth/ABGD7OSUGMRPDWLHPEKJAMDYIEAUFAVCNFSM6AAAAABAIBRQYGVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMYTQNBTHA3TSNRWHA. You are receiving this because you are subscribed to this thread.Message ID: @.***>

This email is confidential, and is for the intended recipient only. Access, disclosure, copying, distribution, or reliance on any of it by anyone outside the intended recipient organisation is prohibited and may be a criminal offence. Please delete if obtained in error and email confirmation to the sender. The views expressed in this email are not necessarily the views of the University of Tasmania, unless clearly intended otherwise.