Event Title

Session 2H: Snails in Seagrass: Benthic habitat predicts endangered queen conch (Lobatus gigas) abundance in The Bahamas

Session Number

Session2H: 1st Presentation

Advisor(s)

Dr. Andrew Kough, Shedd Aquarium

Location

Room A117

Start Date

26-4-2018 10:35 AM

End Date

26-4-2018 11:20 AM

Abstract

The iconic queen conch is integral to the economy and culture of The Bahamas. Indeed, the majority of Bahamian households consume conch flesh weekly, which has resulted in catastrophic declines in abundance. To reverse the decline, effective protections must take into account conch ecology - specifically conch habitat preferences which are hitherto undescribed. Here, we use a massive dataset of conch counts and undersea imagery to build a statistical model that predicts conch abundance from habitat type. Researchers in the field counted conch and captured tens of thousands of geolocated images of the seafloor while surveying 300 km2 of The Bahamas. We implemented a hierarchal categorization system to quantify habitat type in the image dataset. The software ImageJ generated random points within images that were then identified as sand, rubble, seagrass, macroalgae, or invertebrate. Statistical software predicted the variable abundance of mature and immature conch relative to factors habitat type [*and depth and location*]. Adult conch were positively associated with deeper depths, seagrass in excess of XX% and negatively associated with bare substrate. Seagrass was negatively related to invertebrate and rubble coverage. Our results suggest that priority areas for conch-servation should include healthy seagrass bed. The correlations that we pulled from that were a negative association between conch (of any age) and bare sand (R = -0.19, p <0.05), a positive association between adult conch and macroalgae (R = 0.4, p <0.0001), and a positive association between juveniles and seagrass (R = 0.2, p <0.05).

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Apr 26th, 10:35 AM Apr 26th, 11:20 AM

Session 2H: Snails in Seagrass: Benthic habitat predicts endangered queen conch (Lobatus gigas) abundance in The Bahamas

Room A117

The iconic queen conch is integral to the economy and culture of The Bahamas. Indeed, the majority of Bahamian households consume conch flesh weekly, which has resulted in catastrophic declines in abundance. To reverse the decline, effective protections must take into account conch ecology - specifically conch habitat preferences which are hitherto undescribed. Here, we use a massive dataset of conch counts and undersea imagery to build a statistical model that predicts conch abundance from habitat type. Researchers in the field counted conch and captured tens of thousands of geolocated images of the seafloor while surveying 300 km2 of The Bahamas. We implemented a hierarchal categorization system to quantify habitat type in the image dataset. The software ImageJ generated random points within images that were then identified as sand, rubble, seagrass, macroalgae, or invertebrate. Statistical software predicted the variable abundance of mature and immature conch relative to factors habitat type [*and depth and location*]. Adult conch were positively associated with deeper depths, seagrass in excess of XX% and negatively associated with bare substrate. Seagrass was negatively related to invertebrate and rubble coverage. Our results suggest that priority areas for conch-servation should include healthy seagrass bed. The correlations that we pulled from that were a negative association between conch (of any age) and bare sand (R = -0.19, p <0.05), a positive association between adult conch and macroalgae (R = 0.4, p <0.0001), and a positive association between juveniles and seagrass (R = 0.2, p <0.05).