Hot summer helps butterfly numbers critique - Essay Example

Richard Fox the manager of the survey believes that during the summer a majority of the insects were in their early developmental stages and the perfect temperature conditions assisted in their survival and finally gave rise to a large number of adults. The article also confirms that the perfect weather conditions were responsible for attracting immigrant butterflies such as painted lady, clouded yellow, silver Y moth and the rare long-tailed blue. Participants in the survey were asked to look for 21 common butterfly species and the final results saw 15 of these species growing in numbers.

12 out of these 15 species showed a growth of over 50% while only 4 species – the ringlet, marbled white, meadow brown and six-spot burnet moth, showed decrease in their numbers. Mr. Fox inferred that the species which showed decreases in their numbers were ones which have just a single generation every year. Therefore, the number of these species represented the direct offsprings of their parents who had been counted in the last year. However, he confirms that even though the parental numbers in the last count was large, there must have been decline in breeding success giving rise to lower number of off-springs.

The article concludes with the fact that the weather cannot help increase numbers forever and that the number of butterflies in the U.K is gradually declining and the sole way of redressing this problem is to conserve the habitats and inhibit destruction of their range. The author of the article is absolutely accurate in drawing conclusions that butterflies are temperature dependent. Survivorship of butterflies depend on this since if the temperature is not high enough butterflies make the butterflies “more susceptible to predation during roosting and basking periods when they are unable to attain the body temperature needed for vigorous flight” ( Kingsolver,1985,p13).

Hence a decrease in adult population would automatically decrease the population size. Another important role of temperature is its role in fecundity. A study conducted by Karlsson and Wiklund showed that lifelong fecundity of butterflies in relation to temperature was bell shaped where for open landscape butterflies fecundity was optimal at around 30 degrees (Karlsson & Wiklund,2005,p99).Studies also suggest that butterfly fecundity is controlled by temperature at two stages- egg maturation and female ovipositing (Berger et al,2008,p523).

Therefore it is obvious, that since butterflies are temperature dependent, high numbers of emigration as observed because of the prevalent heat wave in the region which attracted butterflies from less suitable weather regions. The article also suggests a solution to the declination in the number of butterflies in the U.K. i.e. prohibiting habitat destruction. It is true that destruction of natural habitat has been the primary reason for decline of the butterfly population. Species richness of butterflies has decreased rapidly in places where habitat destruction is highest (Forister et al, 2010, p2088).

Climate change has also been a major cause of habitat destruction since the changes in climatic conditions alters the vegetation of the habitats and destruction of the biotopes that the butterflies are accustomed to thereby hastening butterfly