Fig 1.
A wild male melon fly, Zeugodacus cucurbitae, with a harmonic radar tag attached.
The tag shown weighed approximately 0.8 mg and was fabricated from a diode and superelastic nitinol wire.
Fig 2.
Flight directions and lengths of HR tagged Zeugodacus cucurbitae for experiment 2 (field cage).
Each replicate consisted of a series of 10 flights with a single tagged fly. Blue arrows represent individual flights, while red arrows show the mean flight direction and length.
Fig 3.
Combined pseudo-turning angles of HR tagged Zeugodacus cucurbitae for experiment 2 (A) and experiment 3 (B). A turning angle of zero indicated that a fly flew in the same direction as the directly previous flight. Combined turning angles were non-random by both Rayleigh and Hermans-Rasson tests, showed no right-left bias, but indicate a pronounced bias towards moving within 90° left or right of the directly previous flight.
Fig 4.
Melon fly, Zeugodacus cucurbitae, flight step-distances for experiment 2–5.
Different letters, in parentheses, indicate significant differences by ANOVA followed by means separations with Student-Newman-Keuls (P = 0.05).
Fig 5.
Flight directions and lengths of HR tagged Zeugodacus cucurbitae for experiment 3 (field cage).
Each replicate consisted of a series of 10 flights with a single tagged fly. Blue arrows represent individual flights, while red arrows show the mean flight direction and length.
Fig 6.
HR tagged Zeugodacus cucurbitae flight directions and lengths for experiment 4 (papaya field).
Colored arrows represent a series of 5–10 flights for a single tagged fly. The large black arrow shows the mean wind direction for the duration of tracking. When all flights were taken together, flight directions were not homogeneous but showed directionality (P < 0.001, Rayleigh test; P < 0.001, Hermans-Rasson test) and a unimodal distribution correlated with the mean wind direction (P < 0.001, V-test).
Fig 7.
Flight directions and lengths of HR tagged Zeugodacus cucurbitae for experiment 4 (papaya field).
Each replicate consisted of a series of 5–10 flights with a single tagged fly. Blue arrows represent individual flights, while red arrows show the mean flight direction and length.
Fig 8.
Combined turning angles of HR tagged Zeugodacus cucurbitae for experiment 4 (papaya).
A turning angle of zero indicated that a fly flew in the same direction as the directly previous flight. Combined turning angles were non-random ( = 0.419, P < 0.001, Rayleigh test, P = 0.001, Hermans-Rasson test), showed no right-left bias (P = 0.735, chi-squared test), but showed a pronounced “forward” movement bias (P < 0.001, chi-squared test).
Fig 9.
Tagged melon fly, Zeugodacus cucurbitae, release points (black center with yellow or white border) and landing points (yellow or white dots) at Lokahi Park, Hilo, HI.
Yellow and white arrows indicate the mean wind direction during fly releases. Source: U.S. Geological Survey, 2011, USGS High Resolution State Orthoimagery for the East Side of Hawaii Island: 05QKB820780_200912_0x5000m_CL_1: U.S. Geological Survey.