As previously described, out of the 14 variables tested, 4 were found to have a significant effect on the amount of Eastern Curlews present within each Quadrat. The first variable, the penetrometer resistance was found to have a negative effect on the amount present. This means that the Eastern Curlews had a preference for softer substrate. This can be attributed to how they source their food, which is present in the substrate. The more resistance the substrate has, the harder and more energy required to reach the food needed. This tied back to migratory bird’s considerations and how their habitat is influenced by their migration as they aim to reduce the amount of energy expended, especially on retrieving food. This was also proven in previous literature, such as the 2007 paper written by Andrew Geering which shows that the Eastern Curlew has a preference for less resistance in the substrate.
The hydrometer reading found there to be very similar substrate texture throughout all 22 quadrats with 17 recording a reading of 0 which is a composition of 100% sand and 5 recording a composition of 99.95% sand.
The wind speed was found to have a positive significant effect with more curlews present during more wind. This goes against previous literature by Andrew Geering. Geering states that “Wind can dry out the substrate causing prey to retreat and that the effects of win conceal prey” (Geering, 2009). The correlation between wind speed and amount of eastern Curlews can be attributed towards timing. Earlier in the study, there were more Curlew present on the mudflats as this was at the earlier stages of migration. However, also earlier in the study, there were high amounts of wind contributed by an ex cyclone. As higher wind was observed during the time in which more birds were present and thus observed, it can be proven that this factor is uncertain, although it was found to be significant. This was shown through high error bars present on the graphical presentation of this wind speed effect. The amount of time to low tide was observed to have a significant negative relation to Eastern Curlew density. …show more content…
There are two hypotheses for why this factor occurred. The first is that as low tide gets closer, the birds become further away and thus harder to see. This variable may have been influenced by the amount of visibility and thus a more powerful spotting scope is recommended for future studies. The second hypothesis is that as the birds migrated, there were less present and therefore it took a quicker amount of time to count the amount of birds and thus there might be a relation between the birds migrating and quicker sampling times which could have been the influencing factor in this significant variable. As the penetrometer and hydrometer readings had an effect showing that the Curlews had a preference for softer substrate, it was unexpected to find no correlation between rock coverage and a lower amount present. This might be due to low amounts of rock coverage in the Victoria point area and thus not able to have a significant effect on the results. However, as this was a pure observational estimate, human error might be a contributing factor. Considerations for a study next time would be to start counting the amount of birds in earlier months, such as January, this would
The hydrometer reading found there to be very similar substrate texture throughout all 22 quadrats with 17 recording a reading of 0 which is a composition of 100% sand and 5 recording a composition of 99.95% sand.
The wind speed was found to have a positive significant effect with more curlews present during more wind. This goes against previous literature by Andrew Geering. Geering states that “Wind can dry out the substrate causing prey to retreat and that the effects of win conceal prey” (Geering, 2009). The correlation between wind speed and amount of eastern Curlews can be attributed towards timing. Earlier in the study, there were more Curlew present on the mudflats as this was at the earlier stages of migration. However, also earlier in the study, there were high amounts of wind contributed by an ex cyclone. As higher wind was observed during the time in which more birds were present and thus observed, it can be proven that this factor is uncertain, although it was found to be significant. This was shown through high error bars present on the graphical presentation of this wind speed effect. The amount of time to low tide was observed to have a significant negative relation to Eastern Curlew density. …show more content…
There are two hypotheses for why this factor occurred. The first is that as low tide gets closer, the birds become further away and thus harder to see. This variable may have been influenced by the amount of visibility and thus a more powerful spotting scope is recommended for future studies. The second hypothesis is that as the birds migrated, there were less present and therefore it took a quicker amount of time to count the amount of birds and thus there might be a relation between the birds migrating and quicker sampling times which could have been the influencing factor in this significant variable. As the penetrometer and hydrometer readings had an effect showing that the Curlews had a preference for softer substrate, it was unexpected to find no correlation between rock coverage and a lower amount present. This might be due to low amounts of rock coverage in the Victoria point area and thus not able to have a significant effect on the results. However, as this was a pure observational estimate, human error might be a contributing factor. Considerations for a study next time would be to start counting the amount of birds in earlier months, such as January, this would