tag:blogger.com,1999:blog-36324352.post4591166425543327995..comments2023-10-16T02:44:53.114+12:00Comments on The Best Shark Dive in the World!: Census of the GWS in Gaansbai - Paper!Andrew Cumminghttp://www.blogger.com/profile/14675497080700112390noreply@blogger.comBlogger14125tag:blogger.com,1999:blog-36324352.post-10224511519226336282013-06-19T19:15:20.624+12:002013-06-19T19:15:20.624+12:00Later , elsewhere.
Good blog.Later , elsewhere.<br /><br />Good blog.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-36324352.post-39816930925051838622013-06-19T14:21:51.004+12:002013-06-19T14:21:51.004+12:00Maybe just state what you want to state and be don...Maybe just state what you want to state and be done with it?DaSharkhttps://www.blogger.com/profile/06787762757245289307noreply@blogger.comtag:blogger.com,1999:blog-36324352.post-36079399877771171692013-06-19T02:43:50.758+12:002013-06-19T02:43:50.758+12:00According to the curve : in the beginning every se...According to the curve : in the beginning every second shark is a new one and in the end every third shark or so is a new one ?<br /><br />So maybe there are at least 2 more reasons why the curve is not quite flattening ?<br /><br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-36324352.post-25124827233977311772013-06-18T21:03:05.299+12:002013-06-18T21:03:05.299+12:00Yep, the riddler and DaShark are on to something h...Yep, the riddler and DaShark are on to something here! <br /><br />There are actually three possibilities why our discovery curves doesn't fall perfectly flat, they could be:<br /><br />1) Constant recruitment in the population - unlikely <br />2) The study has not identified every individual in the system - which would be fairly incredible considering the dataset - but will be addressed Michelle W.noreply@blogger.comtag:blogger.com,1999:blog-36324352.post-27337113428786513652013-06-18T16:04:27.900+12:002013-06-18T16:04:27.900+12:00Phewww... so it looks like I'm not totally fos...Phewww... so it looks like I'm not totally fossilized quite yet... :)<br /><br />Very interesting!<br />Which of course begs the question, how long does one have to count - or does the fact that most sharks are only seen once/a few times (Fig. 1) maybe tell us that the population is completely open with close to zero residency, meaning that one should rather focus on the question of "howDaSharkhttps://www.blogger.com/profile/06787762757245289307noreply@blogger.comtag:blogger.com,1999:blog-36324352.post-24760935499016950492013-06-18T07:46:55.873+12:002013-06-18T07:46:55.873+12:00yes indeed, curve should go flat ... theoretically...yes indeed, curve should go flat ... theoretically<br /><br />patience for the rest :-)<br /><br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-36324352.post-72846439477371605802013-06-18T07:29:16.937+12:002013-06-18T07:29:16.937+12:00Aahh Anonymous - riddles riddles! :)
But OK lemme...Aahh Anonymous - riddles riddles! :)<br /><br />But OK lemme try: <br />One would expect a lot of detections of new sharks at the start and over time, once more and more sharks are being identified, diminishing returns.<br /><br />Hence, the curve should be logarithmic, i.e steep at the beginning and flat at the end.<br /><br />Because the curve is not plateauing, one could argue that not all DaSharkhttps://www.blogger.com/profile/06787762757245289307noreply@blogger.comtag:blogger.com,1999:blog-36324352.post-35615097819667326542013-06-17T18:03:23.555+12:002013-06-17T18:03:23.555+12:00Think carefully about the discovery curve - figure...Think carefully about the discovery curve - figure 2.<br /><br />and what has been omitted from the paper.<br /><br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-36324352.post-3679825286311869212013-06-17T14:18:48.538+12:002013-06-17T14:18:48.538+12:00@ Anonymous
I'm not gonna post your comment &q...@ Anonymous<br />I'm not gonna post your comment "as is".<br /><br />But of course I'm intrigued.<br />Mind elaborating on the scientific aspect whilst forgetting about the BTWs?DaSharkhttps://www.blogger.com/profile/06787762757245289307noreply@blogger.comtag:blogger.com,1999:blog-36324352.post-49081773151425460312013-06-16T20:55:44.483+12:002013-06-16T20:55:44.483+12:00To DaShark and Michelle: I wasn't saying the p...To DaShark and Michelle: I wasn't saying the paper is not good... It's a good paper (with a better methodology than the one of Chapple et al.). And it's a good baseline for GWS census in SA (a country where there is a lot of data, contrary to what you say Michelle..) and if other aggregation sites such as False Bay or Mossel Bay conduct the same analysis, compring these will add Unknownhttps://www.blogger.com/profile/17056627788644115858noreply@blogger.comtag:blogger.com,1999:blog-36324352.post-83381358981988970572013-06-16T14:41:45.956+12:002013-06-16T14:41:45.956+12:00No thank YOU Michelle!
Fine re the accuracy of yo...No thank YOU Michelle!<br /><br />Fine re the accuracy of your mark-recapture analysis.<br />As I said I dunno about GWS (thank god for prophylactic <i>caveats</i> huh! :)) and also, the long uninterrupted observation period and the fact that contrary to Chapple, you did not only deploy decoys but also chum and bait are quite convincing!<br /><br />I'm looking forward to the nationwide censusDaSharkhttps://www.blogger.com/profile/06787762757245289307noreply@blogger.comtag:blogger.com,1999:blog-36324352.post-66978801709311040342013-06-16T01:11:01.437+12:002013-06-16T01:11:01.437+12:00Thanks for the analysis DaShark, and since I know ...Thanks for the analysis DaShark, and since I know he reads the blog too, thanks for the comments Dr.D!<br /><br />It's important to remember that mark-recapture analysis assumes that every animal you documented survived your study period. While our count of 532 which became the super pop. estimate of 908 may seem quite large, it assumes all sharks survived the study period. We know at leastMichelle W.http://www.dict.org.zanoreply@blogger.comtag:blogger.com,1999:blog-36324352.post-50930313419766377802013-06-15T22:09:23.476+12:002013-06-15T22:09:23.476+12:00I actually like the paper!
The authors do not sta...I actually <b>like</b> the paper!<br /><br />The authors do not state that it is anything more than a census for Gaansbai - and you are right, the method is excellent for detecting trends over time.<br /><br />The problem IMO is the infographic that infers that the global status of GWS may be somehow dramatic, an assertion the paper does neither suggest nor support.<br /><br />In reality, most DaSharkhttps://www.blogger.com/profile/06787762757245289307noreply@blogger.comtag:blogger.com,1999:blog-36324352.post-60593139273146956682013-06-15T21:49:59.004+12:002013-06-15T21:49:59.004+12:00Great analysis Mike, as always..; for this paper I...Great analysis Mike, as always..; for this paper I completely agree with you and your causion. Everybody use this info to share the idea that GWS are in low numbers in SA, but this estimate is only restricted to Gansbaii and 800-1000 GWS at on aggregation site is quite important for a top predator... also I thing the methods revealed a lot of incertaintly in the last papers... But it's a goodUnknownhttps://www.blogger.com/profile/17056627788644115858noreply@blogger.com