Thanks for all of this, Melanie, from your remarks at the top to your information on kelp. It seems our personal habitats have much in common, and help is another. We're fortunate to still have some robust help forests around the island and elsewhere in the sound. I'm planning to snorkel through one next summer.
Hakai Magazine out of Victoria BC does some great writing on kelp. Rather then send you a bunch of links, here's the search result list.
Wonderful reporting. Thank you for the detailed explanations for those of us (me) who are ignorant of the destruction of sediment and why kelp is crucial.
Please be aware the cause of kina barrens is not universally accepted to be loss of large predators, including snapper and rock lobster. A quick search of the literature will demonstrate, despite a recent high court case finding Fisheries NZ was negligent setting quotas. However, if correct the current surge of packhorse lobster on the North East coast of NZ should see a rapid change.
On another off topic matter, I use an app called Windy for weather forecasting which has the option of showing where fires are in the world. The Sahal region of Africa is almost solid fire, as with the North and East of Australia.
Thanks Alan, that's really interesting. Is the difference of view specifically in relation to kina barrens, or does it relate to urchin barrens more generally? Declines in kelp and other seaweeds have definitely been linked with other factors than urchin grazing, like climate change and sediment. And increases in urchin population have been linked to factors other than predators in a few cases (one interesting one in the Poor Knights. But I haven't found a lot about other causes. If you've got any suggestions, post me a link.
Windy looks fascinating. I can see myself losing hours there... Australia's looking at a rough fire season, I've been hearing.
Hi Melanie, I'm not sure there is a distinction between kina barrens and urchin barrens; kina being the Maori name for urchin.
Here are a couple of papers relating to the topic:
N. L. Andrew, A. B. MacDiarmid Interrelations between sea urchins and spiny lobsters in northeastern New Zealand https://www.int-res.com/articles/meps/70/m070p211.pdf “…suggest that predation by Jasus [Edwardsii] is not of sufficient magnitude to substantially alter sea urchin population size…” and that “…changes in the abundance of one species (for whatever reason) would not lead to changes in the local abundance of the other…”
Shears NT, Babcock R C (2004): Indirect effects of marine reserve protection on New Zealand's rocky coastal marine communities. https://www.doc.govt.nz/globalassets/documents/science-and-technical/dsis192.pdf also found that “…grazers [including kina] do not appear to play an important role in structuring algal communities…” and that “…the effects of predators on algal assemblages resulting from marine reserve protection are likely to be subtle…”
Thanks, Melanie - I've never seen a kelp forest up close but have seen photos, which are pretty stunning. It's amazing how each ecological niche is a bunch of interlocking puzzle pieces in such a delicate balance - and how far off that balance is now, in so many places.
There's also kelp off the coast of Massachusetts, where I went on some vacation trips as a kid. Not sure how much, though.
Thank you for this information, disheartening as it is. When we forget that everything is connected, we set up chain reactions that can be devastating.
Thanks for all of this, Melanie, from your remarks at the top to your information on kelp. It seems our personal habitats have much in common, and help is another. We're fortunate to still have some robust help forests around the island and elsewhere in the sound. I'm planning to snorkel through one next summer.
Hakai Magazine out of Victoria BC does some great writing on kelp. Rather then send you a bunch of links, here's the search result list.
https://hakaimagazine.com/?s=kelp+
Thanks John, I'll check that out. Hakai Magazine has some great stuff.
Wonderful reporting. Thank you for the detailed explanations for those of us (me) who are ignorant of the destruction of sediment and why kelp is crucial.
Thank you, I really appreciate it.
Interesting story, thanks Melanie.
Please be aware the cause of kina barrens is not universally accepted to be loss of large predators, including snapper and rock lobster. A quick search of the literature will demonstrate, despite a recent high court case finding Fisheries NZ was negligent setting quotas. However, if correct the current surge of packhorse lobster on the North East coast of NZ should see a rapid change.
On another off topic matter, I use an app called Windy for weather forecasting which has the option of showing where fires are in the world. The Sahal region of Africa is almost solid fire, as with the North and East of Australia.
Regards, Alan.
Thanks Alan, that's really interesting. Is the difference of view specifically in relation to kina barrens, or does it relate to urchin barrens more generally? Declines in kelp and other seaweeds have definitely been linked with other factors than urchin grazing, like climate change and sediment. And increases in urchin population have been linked to factors other than predators in a few cases (one interesting one in the Poor Knights. But I haven't found a lot about other causes. If you've got any suggestions, post me a link.
Windy looks fascinating. I can see myself losing hours there... Australia's looking at a rough fire season, I've been hearing.
Hi Melanie, I'm not sure there is a distinction between kina barrens and urchin barrens; kina being the Maori name for urchin.
Here are a couple of papers relating to the topic:
N. L. Andrew, A. B. MacDiarmid Interrelations between sea urchins and spiny lobsters in northeastern New Zealand https://www.int-res.com/articles/meps/70/m070p211.pdf “…suggest that predation by Jasus [Edwardsii] is not of sufficient magnitude to substantially alter sea urchin population size…” and that “…changes in the abundance of one species (for whatever reason) would not lead to changes in the local abundance of the other…”
Shears NT, Babcock R C (2004): Indirect effects of marine reserve protection on New Zealand's rocky coastal marine communities. https://www.doc.govt.nz/globalassets/documents/science-and-technical/dsis192.pdf also found that “…grazers [including kina] do not appear to play an important role in structuring algal communities…” and that “…the effects of predators on algal assemblages resulting from marine reserve protection are likely to be subtle…”
Thanks, Melanie - I've never seen a kelp forest up close but have seen photos, which are pretty stunning. It's amazing how each ecological niche is a bunch of interlocking puzzle pieces in such a delicate balance - and how far off that balance is now, in so many places.
There's also kelp off the coast of Massachusetts, where I went on some vacation trips as a kid. Not sure how much, though.
Thank you for this information, disheartening as it is. When we forget that everything is connected, we set up chain reactions that can be devastating.
Joyce, I agree. And your comments apply both to the kelp forests as well as the "Substack Nazis" issue Melanie opened with...